<PAGE>   1
                                                                Exhibit 4.6


                       FIFTH AMENDMENT TO CREDIT AGREEMENT
                       -----------------------------------


                  THIS FIFTH AMENDMENT TO CREDIT AGREEMENT, dated as of March
___, 1999, (this "Fifth Amendment"), is by and among OLYMPIC STEEL, INC., an
Ohio corporation ("Borrower"), and NATIONAL CITY BANK ("NCB") and the group of
other banks signatory hereto or that become parties to the Credit Agreement
hereafter identified by amendment or supplement thereto (NCB and the banks
comprising such group at any specific time, hereinafter referred to as the
"Banks") and NATIONAL CITY BANK, as agent for the Banks (in that capacity,
"NCB-Agent").

                                    RECITALS
                                    --------

                  A. Borrower, the Banks and NCB-Agent entered into a Credit
Agreement, dated as of October 4, 1996 (the "Credit Agreement"), pursuant to
which Borrower may obtain, among other things, (i) loans ratably from the Banks
that are on a revolving credit basis and (ii) subject LCs issued by NCB in which
the Banks agree to ratably share the obligations in respect thereof, in each
case until the expiration date.

                  B. Borrower, the Banks and NCB-Agent entered into the First
Amendment to Credit Agreement, dated as of January 24, 1997 (the "First
Amendment"), in order to increase the amount of the commitments by the Banks for
subject revolving credit loans and additional subject LCs by Ten Million Dollars
($10,000,000) and to permit Borrower to make certain joint venture investments
and guarantees of indebtedness of the joint venture entities.

                  C. Borrower, the Banks and NCB-Agent entered into the Second
Amendment to Credit Agreement, dated as of May 30, 1997 (the "Second
Amendment"), in order to increase the amount of the commitments by the Banks for
subject revolving credit loans and additional subject LCs by Eight Million
Dollars ($8,000,000), to add a commitment by Banks for new Series A term loans
in the amount of Seventeen Million Dollars ($17,000,000), to permit certain
borrowing from other lenders, to permit the Borrower to allow certain of its
property to become encumbered by liens in favor of other lenders and to extend
the expiration date to June 30, 2000.

                  D. Borrower, the Banks and NCB-Agent entered into the Third
Amendment to Credit Agreement, dated as of July 14, 1997 (the "Third Amendment")
in order to add an additional bank as a party to Credit Agreement, to adjust the
ratable share of the obligations among the Banks which were original parties to
the Credit Agreement, to decrease the aggregate amount of the commitments by the
Banks for existing subject LCs, and to make appropriate changes to the Credit
Agreement in recognition that some or all of the proceeds of the subject loans
would be used by a new subsidiary of Borrower, Olympic Steel Iowa, Inc., for the
purpose of acquiring land and constructing a temper mill facility in Bettendorf,
Iowa.

                  E. Borrower, the Banks and NCB-Agent entered into the Fourth
Amendment to Credit Agreement, dated December 8, 1998 (the "Fourth Amendment")
in order to authorize Borrower to borrow funds from Mellon Bank, N.A.
("Mellon"), one of the Banks, pursuant to a discretionary Swing Line of Credit
facility (the "Swing Loan") as an additional exception to the prohibition
against incurring indebtedness under Section 3D.02 of the Credit Agreement; to
grant

<PAGE>   2



 to Mellon a one-time right to have the Banks refund the outstanding Swing
Loan as a subject revolving credit loan; and to adjust Mellon's subject
commitment with respect to the subject loans made pursuant to the Credit
Agreement until such time as the Swing Loan is refunded at Mellon's request by a
subject revolving credit loan.

                  F. Borrower, the Banks and NCB-Agent desire to again amend the
Credit Agreement by this Fifth Amendment to Credit Agreement (the "Fifth
Amendment") in order to extend the expiration date until June 30, 2002; to
increase the amount of the series A subject term loan commitment by $4,000,000,
to waive certain covenant requirements and exclude certain charges therefrom and
modify the interest rates payable by Borrower based on Borrower's
EBIT-to-interest ratio.

                                    AGREEMENT
                                    ---------

         Accordingly, the parties have agreed and do hereby agree as follows:

         1. Subsection 2A.01.1 SERIES A TERM LOANS of the Agreement shall be
deleted in its entirety and the following shall be substituted in place thereof:

                  2A.01.1 SERIES A TERM LOANS - (a) The aggregate amount of the
         series A subject term loans shall be an amount up to, but not
         exceeding, Twenty One Million Dollars ($21,000,000). The series A
         subject term loans shall be made and disbursed not more frequently than
         once each calendar month and the aggregate amount thereof shall not
         exceed eighty percent (80%) of costs reasonably incurred and paid by
         Borrower or OSII for construction of a temper mill facility in
         Bettendorf, Iowa (the "Iowa Mill Project"). With each request for a
         series A subject term loan advance, Borrower or OSII shall submit to
         NCB-Agent evidence of such costs so incurred and paid and such other
         information as NCB-Agent may request with respect to the Iowa Mill
         Project including, without limitation, the estimated cost of completing
         the same. The subject commitments for any amount of the series A
         subject term loans not disbursed on or before April 29, 1999, shall
         automatically and immediately expire on April 30, 1999 without any
         notice to Borrower.

                  (b) Beginning May 30, 1999, the outstanding principal amount
         of the series A subject term loans shall be reduced annually prior to
         the expiration date by an amount equal to ten percent (10%) of the
         aggregate amount thereof outstanding and disbursed prior to April 30,
         1999,(for example, if the aggregate amount of the series A subject term
         loans disbursed is $21,000,000, then the amount of each principal
         reduction prior to the expiration date shall be $2,100,000). A
         principal payment of the series A subject term loans shall be made on
         each May 30 commencing on May 30, 1999 with a final payment of the
         entire outstanding amount of the series A subject term loans being due
         and payable on the expiration date.

                  (c) The amount of each Bank's subject commitment to make
         series A subject term loans (which is subject to termination pursuant
         to Section 5B), and the proportion (expressed as a percentage) that it
         bears to all of the subject commitments relating thereto is set forth
         opposite the Bank's name below.

<PAGE>   3


<TABLE>
<CAPTION>

=========================================== ====================================== ==================================
                   Bank                          Series A Subject Term Loan                   Percentage
------------------------------------------- -------------------------------------- ----------------------------------
<S>                                                   <C>                                      <C>
National City Bank                                       $8,400,000                               40%
------------------------------------------- -------------------------------------- ----------------------------------
Comerica Bank                                            $5,250,000                               25%
------------------------------------------- -------------------------------------- ----------------------------------
Mellon Bank, N.A.                                        $4,200,000                               20%
------------------------------------------- -------------------------------------- ----------------------------------
PNC Bank, National Association                           $3,150,000                               15%
------------------------------------------- -------------------------------------- ----------------------------------
Total                                                    $21,000,000                             100%
=========================================== ====================================== ==================================
</TABLE>

                  (d) Anything contained in this subsection 2A.01.1 to the
         contrary notwithstanding, no term loan shall be made or disbursed by
         any of the Banks prior to compliance by Borrower with the conditions
         set forth in section 2B of this Agreement.

         2. Subsection 2A.02 TERM of Credit Agreement shall be deleted in its
entirety and the following shall be substituted in place thereof:

                  2A.02 TERM - The subject commitment of each Bank and the
         subject commitments in the aggregate shall remain in effect until June
         30, 2002 (the "expiration date") EXCEPT that (i) a later expiration
         date may be established from time to time pursuant to subsection 2A.05.
         (ii) the subject commitments shall end in any event upon any earlier
         reduction thereof to zero pursuant to subsection 2A.03 or any earlier
         termination pursuant to Section 5B, (iii) the commitment relating to
         any existing LC shall remain in effect until the stated expiration date
         thereof, even if such date is later than the expiration date; and (iv)
         the commitments for the series A subject term loans not disbursed on or
         prior to April 29, 1999, will expire automatically and immediately on
         April 30, 1999. The series A term loans shall be disbursed pursuant to
         subsection 2A.01.1(a).

         3. Subsection 2A.06 MELLON SWING LOAN, REFUNDING THEREOF, AND
ADJUSTMENT OF SUBJECT COMMITMENTS shall be deleted in its entirety and the
following shall be substituted in place thereof:

                  2A.06    MELLON SWING LOAN, REFUNDING THEREOF, AND ADJUSTMENT 
         OF SUBJECT COMMITMENTS

         (a)      Subject to the terms and conditions of a discretionary Swing
                  Line Loan Agreement, Borrower shall have the right to obtain
                  and have outstanding from time to time the Swing Loan from
                  Mellon in aggregate principal amount not exceeding at any time
                  $16,000,000.00 as such amount may be reduced at Mellon's sole
                  discretion (the "Maximum Swing Loan Amount"). Notwithstanding
                  the provisions of subsection 2A.01 or any other provision
                  hereof, at all times during the Swing Loan Availability Period
                  (as defined in Subsection (b) below), the aggregate amount of
                  the commitments by the Banks for subject revolving credit
                  loans and additional subject LCs and Series A subject term
                  loans 

<PAGE>   4

                  shall be reduced by the value of the Maximum Swing Loan
                  Amount, whether or not there is any amount outstanding under
                  the Swing Loan. Such reduction shall not affect the commitment
                  fees payable pursuant to subsection 2A.04 hereof.

         (b)      (i)      Except as set forth in subsection (b)(ii) below,
                           during the period (the "Swing Loan Availability
                           Period") from and after the effective date hereof and
                           until the earlier of (A) the date on which the Banks
                           refund the Swing Loan pursuant to paragraph (c) below
                           (the "Refunding Date") or (B) the expiration date, or
                           (C) the date Mellon terminates the Swing Loan's
                           availability to Borrower (a "Swing Loan Availability
                           Termination"), the proportion (expressed as a
                           percentage) that the amount of the subject commitment
                           of Mellon bears to the aggregate of all subject
                           commitments pursuant to the Credit Agreement shall be
                           reduced to eleven percent (11%) and the amount of
                           each Bank's commitment to make subject revolving
                           credit loans and additional subject LCs and Series A
                           subject term loans to Borrower, and the proportion
                           (expressed as a percentage) that each Bank's subject
                           commitment bears to all of the subject commitments,
                           are set forth opposite the Bank's name on SCHEDULE
                           2A.06 hereto dated March, 1999.

                  (ii)     In the event that during the Swing Loan Availability
                           Period, Mellon elects to reduce the Maximum Swing
                           Loan Amount (a "Swing Loan Reduction"), the aggregate
                           subject commitment of the Banks shall increase by the
                           amount of the reduction and the subject commitment of
                           each Bank shall be adjusted to the percentages of the
                           aggregate subject commitments of the Banks set forth
                           in SCHEDULE 2A.06(b)(ii) hereto dated March, 1999.

         (c)      On any day when the Swing Loan is outstanding prior to the
                  expiration date (whether before or after the maturity thereof
                  or the occurrence of an event of default under the Swing Loan
                  Agreement or under this Credit Agreement), Mellon shall have
                  the one-time right to request that the Banks refund the
                  outstanding principal amount of the Swing Loan and any accrued
                  but unpaid interest thereon as a subject revolving credit loan
                  obtained by Borrower by written notice thereof by Mellon to
                  NCB-Agent, the Banks and Borrower not later than 1:00 p.m.
                  Cleveland time on a Banking Day. Any such notice by Mellon
                  shall be deemed to be a "credit request" by Borrower for
                  purposes of subsection 2D.01 of the Credit Agreement for
                  disbursement of a sum equal to the principal amount of the
                  Swing Loan and accrued but unpaid interest thereon. Promptly
                  following receipt of such notice from Mellon to NCB-Agent,
                  NCB-Agent shall promptly notify each Bank thereof (by
                  facsimile or telephone, confirmed in writing) and the amount
                  required from each Bank on account thereof following which
                  each Bank shall cause the required subject loan to be
                  disbursed to NCB-Agent, in immediately available funds, not
                  later than 12:00 Noon, Cleveland time, on the next Banking
                  Day, to be held for the benefit of Mellon at its direction,
                  provided, however, the amount required from each Bank shall in
                  no event exceed such Bank's subject commitment with respect to
                  the subject revolving credit loan to

<PAGE>   5

                  Borrower pursuant to the Credit Agreement. On such next
                  Banking Day, the subject commitments of Mellon and the other
                  Banks in the subject loans shall revert to the amounts and
                  percentages set forth on SCHEDULE 2A.01 of the Credit
                  Agreement and in Subsection 2A.01.1(c) of the Credit
                  Agreement. The obligations of the Banks to refund the Swing
                  Loan in accordance with this Subsection 2A.06(c) shall be
                  absolute and unconditional and not subject to Section 2.D of
                  the Credit Agreement and irrespective of the existence of an
                  event of default by any Bank or Borrower hereunder or under
                  the Swing Loan Agreement or any set-off, counterclaim,
                  recoupment, defense or other right such Bank may have against
                  Mellon or the Borrower or any adverse change in Borrower's
                  condition, financial or otherwise or any other circumstance,
                  happening or event whatsoever.

         (d)      Mellon shall promptly give NCB-Agent and the other Banks
                  written notice of a Swing Loan Reduction or Swing Loan
                  Availability Termination. On the next Banking Day thereafter,
                  the subject commitments of Mellon and the other Banks in the
                  subject loans shall change, in the case of a Swing Loan
                  Reduction, to the percentages of the aggregate subject
                  commitments of the Banks as set forth in SCHEDULE 2A.06(b)(ii)
                  hereto or, in the case of a Swing Loan Availability
                  Termination, to the amounts and percentages set forth in
                  Schedule 2A.01 of the Credit Agreement and in subsection
                  2A.01.1(c) of the Credit Agreement.

         (e)      Mellon shall discontinue making further advances of the Swing
                  Loan as promptly as practicable after receipt of notice from
                  NCB-Agent that the Banks, other than Mellon, require
                  discontinuation of such further advances as a result of an
                  Event of Default under the Credit Agreement.

         (f)      Notwithstanding any provision to the contrary contained in the
                  Credit Agreement, no part of this subsection 2A.06 may be
                  modified or amended without the prior written consent of
                  Mellon.

         4. Subsection 2B.01 SUBJECT NOTES of the Credit Agreement shall be
deleted in its entirety and the following shall be substituted in place thereof:

                  2B.01 SUBJECT NOTES - Each Bank's subject revolving credit
         loan and participation in respect of additional subject LCs and
         existing subject LCs shall be evidenced by subject notes executed and
         delivered by Borrower, payable to the order of that Bank aggregating in
         the principal amount equal to the dollar amount of that Bank's
         aggregate subject commitment therefor set forth in subsection 2A.01.
         Each subject note shall be in the form and substance of EXHIBIT 2B.01
         with the blanks appropriately completed. Each of the subject term loans
         by each Bank shall be evidenced by a separate subject note or notes
         executed and delivered by Borrower, payable to the order of the Bank in
         principal amount equal to the dollar amount of Bank's subject
         commitment therefor; each such note shall be in form and substance of
         EXHIBIT 2B.01T with the blanks appropriately completed. The subject
         term loans are represented by series A subject term loan notes dated
         July 14, 1997 aggregating $17,000,000.00 and supplemental series A
         

<PAGE>   6

         subject term loan notes dated as of the date hereof aggregating
         $4,360,000.00 which includes a supplemental series A subject term loan
         note in the principal amount of $800,000.00 payable to Mellon for the
         maximum dollar amount of its subject commitment with respect to the
         increase in the aggregate series A subject term loan commitment of the
         Banks evidenced by the supplemental series A subject term loan notes
         dated as of the date hereof if the subject commitment of each of the
         Banks with respect to the series A subject term loan were adjusted
         pursuant to subsection 2A.06 hereof.

         (a)      Whenever Borrower obtains a series of subject loans pursuant
                  to this Agreement, each Bank shall make an appropriate entry
                  into a loan account maintained in that Bank's books and
                  records. Each entry shall be prima facie evidence of the data
                  so entered; but such entries shall not be a condition to
                  Borrower's obligation to pay.

         (b)      No holder of any subject note shall transfer a subject note,
                  or seek a judgment or file a proof of claim based on a subject
                  note without in each case first endorsing the subject note to
                  reflect the true amount owing thereon.

         5. Subsection 2B.07 INTEREST RATES AND LETTER OF CREDIT COMMISSIONS of
the Credit Agreement shall be deleted in its entirety and the following shall be
substituted in place thereof:

                  2B.07 INTEREST RATES AND LETTER OF CREDIT COMMISSIONS - (a)
          Prior to maturity, the principal of subject revolving credit loans and
          term loans shall bear interest at the per annum rates and the
          commissions on the subject letters of credit (in both cases, computed
          in accordance with subsection 8.10) as calculated based on the
          following:

                  (i) Prime rate loans shall bear interest at a fluctuating rate
         equal to the prime rate from time to time in effect, with each change
         in the prime rate automatically and immediately changing the rate
         thereafter applicable to the prime rate loans plus the applicable prime
         rate margin as determined in accordance with the following table;

                  (ii) LIBOR loans shall bear interest at a rate equal to the
         LIBOR pre-margin rate in effect at the start of the applicable contract
         period (except that any change in the FRB reserve percentage shall
         automatically and immediately change the LIBOR pre-margin rate
         thereafter applicable to the LIBOR loans) plus the applicable LIBOR
         margin as determined in accordance with the following table;

                  (iii) Commissions on existing subject LCs have been paid in
         advance through the respective dates set forth on EXHIBIT 2(B).07(iii).
         Commencing after such dates commissions on all subject LCs shall be
         adjusted quarterly on the last business day of each March, June,
         September and December of each year on the basis of the applicable
         percentage as determined in accordance with the following table:


<PAGE>   7
<TABLE>
<CAPTION>

============================= ============================== ===================================== ==================

<S>                            <C>                        <C>                                       <C>
     If the Borrower's             and the Borrower's          Then, both the applicable LIBOR          And the
    Liabilities-to-Worth         EBIT-to-Interest Ratio               LIBOR margin and the              applicable
         Ratio is:                         is:                     applicable letter of credit          Prime rate
                                                                  commission shall be equal to:           margin 
                                                                                                          equals:
----------------------------- ------------------------------ ------------------------------------- ------------------
<S>                         <C>                           <C>                                           <C>
less than or equal to         Greater than or  equal  to     62.5 basis points                             0
 .75:1                         4.50:1
----------------------------- ------------------------------ ------------------------------------- ------------------
greater than .75:1 but less   Less than 4.50:1 but greater   75 basis points                               0
than or equal to 1.25:1       than or equal to 3.50:1
----------------------------- ------------------------------ ------------------------------------- ------------------
Greater than 1.25:1 but       Less than 3.50:1 but greater   100 basis points                              0
less than or equal to 1.75:1  than or equal to 3.00:1
----------------------------- ------------------------------ ------------------------------------- ------------------
greater than 1.75:1           Less than 3.00:1 but greater   125 basis points                              0
                              than or equal to 2.50:1
----------------------------- ------------------------------ ------------------------------------- ------------------
greater than 1.75:1           Less than 2.50:1               150 basis points                              0
============================= ============================== ===================================== ==================
</TABLE>

          Both the liabilities-to-worth ratio and EBIT-to-interest ratio must be
         satisfied in order for the corresponding applicable prime rate margin,
         applicable LIBOR margin and applicable letter of credit commission to
         be effective, and if either the specific liabilities-to-worth ratio or
         EBIT-to-interest ratio is not satisfied, then the next highest prime
         rate margin, LIBOR margin or applicable letter of credit commission
         shall be applicable.

         (b)      After maturity (whether occurring by lapse of time or by
                  acceleration), the prime rate loans shall bear interest at a
                  fluctuating rate equal to the prime rate from time to time in
                  effect plus two percent (2%) per annum; PROVIDED, that in no
                  event shall the rate applicable to the prime rate
                  loans after the maturity thereof be less than the rate
                  applicable thereto immediately before maturity and each LIBOR
                  loan shall bear interest computed and payable in the same
                  manner as in the case of prime rate loans EXCEPT that in no
                  event shall any LIBOR loan bear interest after maturity
                  at a lesser rate than that applicable thereto immediately
                  before maturity.

         5. Subsection 3B.03 INTEREST COVERAGE of the Credit Agreement shall be
deleted in its entirety and the following substituted in place thereof:

                  3B.03 INTEREST COVERAGE - On a consolidated statement basis,
         Borrower will not, as at the end of the fiscal quarter during any
         fiscal year of Borrower (commencing with the present year), suffer or
         permit its EBIT-to-interest ratio to be less than two and one-half to
         one (2.50:1) except as hereinafter provided. The Banks waive Borrower's
         compliance with the foregoing EBIT-to-interest ratio requirement as of
         December 31, 1998, and confirm that Borrower's EBIT determined as of
         December 31, 1998, shall not include, for purposes of determining
         Borrower's EBIT-to-interest ratio, the 1998 fiscal year-end asset
         valuation accounting adjustments totaling approximately $19,056,000.00
         to eliminate the carrying value of OSLI's goodwill and to reduce to
         fair market value certain OSLI fixed assets and Borrower's investment
         in the OCR scrap trading joint venture. Further, notwithstanding the
         foregoing, Borrower's EBIT-to-

<PAGE>   8

         interest ratio for the fiscal quarter ending March 31, 1999 shall be
         not less than 1.65:1 and for the fiscal quarter ending June 30, 1999
         shall be not less than 1.90:1. For purposes of calculating this ratio,
         Borrower's interest figure initially was based on the Borrower's actual
         interest expenses for the third quarter of 1996 annualized. On December
         31, 1996, the interest figure was based on such actual expenses for the
         preceding six (6) months annualized. On March 31, 1997, the interest
         figure was based on such actual expenses for the preceding nine (9)
         months annualized. On June 30, 1997, and for every twelve (12) month
         period thereafter, the interest figure was and is to be based on the
         preceding twelve (12) months annualized.

         6. Subsection 3D.04 FIXED ASSETS of the Credit Agreement shall be
deleted in its entirety and the following substituted in its place thereof:

                  3D.04 FIXED ASSETS - Borrower will not, nor permit OSLI or
         OSMI to, invest (net after trade-ins, if any) in any fiscal year in
         fixed assets and leasehold improvements during any fiscal year
         (commencing with 1997) of more than Fifteen Million Dollars
         ($15,000,000). Notwithstanding the foregoing, expenditures made by
         Borrower during 1999 with respect to improving and equipping facilities
         at Chambersburg, Pennsylvania shall be excluded from such limitation to
         the extent financed pursuant to industrial development revenue bonds.

         7. Prior to or at the execution and delivery of this Fifth Amendment,
Borrower shall have complied with or caused compliance with each of the
following:

                   (a) Borrower shall have executed and delivered to the
         appropriate Bank a supplemental series A subject term loan note dated
         as of the date hereof in the following principal amounts which reflect
         the maximum dollar amount of each Bank's share of the increase in the
         aggregate series A subject term loan commitment of the Banks:
<TABLE>
<CAPTION>

           ------------------------------------------------ ---------------------------------------------------------
                                BANK                          SUPPLEMENTAL SERIES A SUBJECT TERM LOAN NOTE AMOUNT
           ------------------------------------------------ ---------------------------------------------------------

           ------------------------------------------------ ---------------------------------------------------------
        <S>                                                                       <C>          
           National City Bank                                                         $1,760,000.00
           ------------------------------------------------ ---------------------------------------------------------
           Comerica Bank                                                               1,120,000.00
           ------------------------------------------------ ---------------------------------------------------------
           Mellon Bank, N.A.                                                             800,000.00
           ------------------------------------------------ ---------------------------------------------------------
           PNC Bank National Association                                                 680,000.00
                                                                                         ----------
           ------------------------------------------------ ---------------------------------------------------------
                             Total                                                    $4,360,000.00
                                                                                      =============
           ------------------------------------------------ ---------------------------------------------------------
</TABLE>

                   (b) OSII shall have executed and delivered to NCB-Agent a
         supplement to the OSII Guaranty of Payment dated July 17, 1997 and OSII
         Security Agreement dated July __, 1998 in form and substance
         satisfactory to NCB-Agent so as to extend the amount of OSII's subject
         guaranty and the security interest securing such subject guaranty to
         include the increased amount of the series A subject term loan
         commitment of the Banks.

                   (c) Borrower's secretary shall have certified to each Bank
         resolutions duly adopted by Borrower's board of directors in respect of
         this Fifth Amendment and the matters

<PAGE>   9

         contemplated hereby and authorizing execution, delivery and performance
         of this Fifth Amendment and the subject notes to be delivered by
         Borrower pursuant to this Fifth Amendment.

                   (d) OSII's secretary shall have certified to each Bank
         resolutions duly adopted by OSII's board of directors authorizing the
         execution, delivery and performance of the supplement to OSII's subject
         guaranty and the OSII Security Agreement dated July __, 1998.

                  (e) Borrower shall pay or cause to be paid to NCB-Agent a
         waiver and amendment fee in the amount of $85,000.00 to be shared
         ratably among the Banks.

         8. From and after the effective date of this Fifth Amendment,
references in the Credit Agreement and the subject notes (as amended by the
First Amendment, the Second Amendment, the Third Amendment, the Fourth Amendment
and this Fifth Amendment thereto or pursuant to such amendments) to the Credit
Agreement shall be deemed to be references to the Credit Agreement as amended by
all such amendments (unless otherwise expressly indicated) and the subject notes
shall be deemed to include the revolving credit loan notes and replacements
thereof and the series A subject term loan notes and the supplemental series A
subject term loan notes executed and delivered pursuant to this Fifth Amendment.

         9. Borrower restates and reaffirms all of its representations and
warranties set forth in Section 4B of the Credit Agreement as of the date
hereof.

         10. This Fifth Amendment and the modifications set forth herein shall
be and become effective as of the date hereof.

         11. The Credit Agreement, as amended by the First Amendment, the Second
Amendment, the Third Amendment and this Fifth Amendment, is hereby ratified and
confirmed.

         12. This Fifth Amendment may be executed in one or more counterparts,
each counterpart to be executed by Borrower, by NCB-Agent and by one or more or
all of the Banks. Each such executed counterpart shall be deemed to be an
executed original for all purposes but all such counterparts taken together
shall constitute one agreement, which agreement constitutes the entire agreement
among the parties hereto with respect to the subject matter hereof.

         13. This Fifth Amendment may be executed by representatives of the
Banks using facsimile signatures and facsimilied signature pages shall in all
respects be binding on all parties hereto and thereto as if such signature pages
were originally delivered. Original signature pages for all facsimilied
signature pages shall be delivered to NCB-Agent not later than March 15, 1999.

         IN WITNESS WHEREOF, the parties have executed this Fifth Amendment as
of the date first above written.


<PAGE>   10

NATIONAL CITY BANK, AGENT                        OLYMPIC STEEL, INC.




By:                                            By:
  -------------------------------                 ----------------------------
     Sean P. Richardson                              Richard T. Marabito
     Vice President                                  Treasurer


NATIONAL CITY BANK                             MELLON BANK, N.A.


By:                                            By:
  ------------------------------                 ----------------------------
     Sean P. Richardson                              John K. Walsh
     Vice President                                  Vice President


COMERICA BANK                                  PNC BANK, NATIONAL ASSOCIATION


By:                                            By:
  ------------------------------                 ----------------------------
     Richard S. Arceci                               Mark W. Rutherford
     Vice President                                  Vice President


<PAGE>   11






                                 SCHEDULE 2A.06
                                 --------------
                                DATED MARCH, 1999

             ADJUSTED SUBJECT COMMITMENTS RESULTING FROM SWING LOAN

       Subject commitments for subject revolving credit loans and subject
                               LCs Schedule 2A.01

<TABLE>
<CAPTION>

-------------------------- ---------------------------- --------------------- ---------------------- --------------
                            Subject revolving credit
          Bank                loans and additional        Existing subject      Aggregate Subject     Percentage
                             subject LCs (excluding             LCs*               Commitment*
                              existing subject LCs)
-------------------------- ---------------------------- --------------------- ---------------------- --------------
<S>                                 <C>                   <C>                    <C>                   <C>
National City Bank                     $22,880,000           $3,556,691             $26,436,691           44%
-------------------------- ---------------------------- --------------------- ---------------------- --------------
Comerica Bank                          $14,560,000           $2,263,349             $16,823,349           28%
-------------------------- ---------------------------- --------------------- ---------------------- --------------
Mellon Bank, N.A.                       $5,720,000             $889,173              $6,609,173           11%
-------------------------- ---------------------------- --------------------- ---------------------- --------------
PNC Bank, National
Association                             $8,840,000           $1,374,176             $10,214,176           17%
-------------------------- ---------------------------- --------------------- ---------------------- --------------
Total                                  $52,000,000           $8,083,389             $60,083,389          100%
-------------------------- ---------------------------- --------------------- ---------------------- --------------
</TABLE>

* Rounded to the nearest whole dollar (as of 12/03/98).

<TABLE>
<CAPTION>


                             Series A term loan subject commitments Section 2A.01.1(c)

============================================== ====================================== ==============================
                    Bank                            Series A Subject Term Loan                 Percentage
---------------------------------------------- -------------------------------------- ------------------------------
<S>                                                      <C>                                   <C>
National City Bank                                           $9,240,000                            44%
---------------------------------------------- -------------------------------------- ------------------------------
Comerica Bank                                                $5,880,000                            28%
---------------------------------------------- -------------------------------------- ------------------------------
Mellon Bank, N.A.                                            $2,310,000                            11%
---------------------------------------------- -------------------------------------- ------------------------------
PNC Bank, National Association                               $3,570,000                            17%
---------------------------------------------- -------------------------------------- ------------------------------
Total                                                       $21,000,000                           100%
============================================== ====================================== ==============================

</TABLE>


<PAGE>   12



                             SCHEDULE 2A.06(b) (II)
                             ----------------------
                                DATED MARCH, 1999

 ADJUSTMENT OF BANKS' SUBJECT COMMITMENTS AS A RESULT OF A SWING LOAN REDUCTION

<TABLE>
<CAPTION>

------------------------------ ---------------------------------------------------------------------------------------

If the Maximum                        Then the percentage of the aggregate
Swing Loan Amount is:                 subject commitment of the Banks is:

---------------------------------- --------------------- --------------------- --------------------- ---------------------
                                                                                                        PNC BANK 
                                                           NATIONAL CITY           COMERICA             NATIONAL
                                       MELLON BANK         BANK                    BANK                 ASSOCIATION
---------------------------------- --------------------- --------------------- --------------------- ---------------------
<S>                                      <C>                   <C>                   <C>                   <C>
$16,000,000                                 11%                   44%                   28%                   17%
---------------------------------- --------------------- --------------------- --------------------- ---------------------
Less than $16,000,000 but                   12%                   43.5%                 27.7%                 16.8%
greater than or equal to $14,222,222
---------------------------------- --------------------- --------------------- --------------------- ---------------------
Less than $14,222,222 but                   13%                   43%                   27.4%                 16.6%
greater than or equal to $12,444,444
---------------------------------- --------------------- --------------------- --------------------- ---------------------
Less than $12,444,444 but                   14%                   42.5%                 27.1%                 16.4%
greater than or equal to $10,666,667
---------------------------------- --------------------- --------------------- --------------------- ---------------------
Less than $10,666,667 but                   15%                   42.1%                 26.8%                 16.1%
greater than or equal to $8,888,889
---------------------------------- --------------------- --------------------- --------------------- ---------------------
Less than $8,888,889 but                    16%                   41.7%                 26.5%                 15.8%
greater than or equal to $7,111,111
---------------------------------- --------------------- --------------------- --------------------- ---------------------
Less than $7,111,111 but                    17%                   41.3%                 26.1%                 15.6%
greater than or equal to $5,333,333
---------------------------------- --------------------- --------------------- --------------------- ---------------------
Less than $5,333,333 but                    18%                   40.8%                 25.8%                 15.4%
greater than or equal to $3,555,556
---------------------------------- --------------------- --------------------- --------------------- ---------------------
Less than $3,555,556 but                    19%                   40.4%                 25.4%                 15.2%
greater than or equal to $1,777,778
---------------------------------- --------------------- --------------------- --------------------- ---------------------
Less than $1,777,778                        20%                   40%                   25%                   15%
---------------------------------- --------------------- --------------------- --------------------- ---------------------

</TABLE>