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                                  Exhibit 4.2

                       1998 EMPLOYEE STOCK PURCHASE PLAN
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                        MERCURY INTERACTIVE CORPORATION
                       1998 EMPLOYEE STOCK PURCHASE PLAN

                   (Amended and Restated as of May 24, 2000)

          1.    Purpose.  The purpose of the Plan is to provide employees of
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Mercury Interactive Corporation and its Designated Subsidiaries with an
opportunity to purchase Common Stock of Mercury Interactive Corporation through
accumulated payroll deductions. It is the intention of Mercury Interactive
Corporation to have the Plan qualify as an "Employee Stock Purchase Plan" under
Section 423 of the Internal Revenue Code of 1986, as amended. The provisions of
the Plan shall, accordingly, be construed so as to extend and limit
participation in a manner consistent with the requirements of that section of
the Code.

     2.   Definitions.
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          (a)   "Board" means the Board of Directors of Mercury Interactive
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 Corporation.

          (b)   "Code" means the U.S. Internal Revenue Code of 1986, as amended.
                 ----

          (c)   "Common Stock" means the Common Stock of Mercury Interactive
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Corporation.

          (d)   "Company" means Mercury Interactive Corporation, a Delaware
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corporation and (where the context so requires), its Designated Subsidiaries.

          (e)   "Compensation" means all regular straight time earnings, and all
                 ------------
payments for overtime, shift premium, incentive compensation, incentive
payments, bonuses, commissions or other compensation.

          (f)   "Designated Subsidiaries" means the Subsidiaries which have been
                 -----------------------
designated by the Board from time to time in its sole discretion as eligible to
participate in the Plan. As of the date of adoption of the Plan, the Designated
Subsidiaries are Mercury Interactive (Israel) Ltd, Mercury Interactive (Europe)
N.V., Mercury Interactive France S.A.R.L., Mercury Interactive GmbH, and Mercury
Interactive (UK) Ltd. Additional Designated Subsidiaries, as added by the Board,
shall be listed in Appendix I to the Plan.

          (g)   "Employee" means any individual who is an employee of the
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Company or its Designated Subsidiary for purposes of U.S. income tax withholding
under the Code whose customary employment is at least twenty (20) hours per week
and more than five months in any calendar year (including Employees of a
Designated Subsidiary who would, if subject to US. income tax, be an employee
for such purposes). For purposes of the Plan, the employment relationship shall
be treated as continuing intact while the individual is on sick leave or other
leave of absence approved by the Company. Where the period of leave exceeds 90
days and the individual's right to reemployment is not guaranteed either by
statute or by contract, the employment relationship will be deemed to have
terminated on the 91st day of such leave.

          (h)   "Exercise Date" means the date one day prior to the date 6
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months from any Offering Date.

          (i)   "Offering Date" means the first day of each Offering Period of
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the Plan. The first Offering Date under the Plan will be May 20, 1998.

          (j)   "Offering Period" means a 6-month period beginning on the
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Offering Date and ending on the Exercise Date.
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     (k)  "Plan" means this 1998 Employee Stock Purchase Plan as amended and
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restated effective May 24, 2000.

     (l)  "Subsidiary" means a corporation, domestic or foreign, of which not
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less than 50% of the voting shares are held by the Company or a Subsidiary,
whether or not such corporation now exists or is hereafter organized or acquired
by the Company or a Subsidiary.

     (m)  "Trading Day" means a day on which national stock exchanges and the
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National Market System of the National Association of Securities Dealers
Automated Quotation (NASDAQ) System are open for trading.

  3. Eligibility.
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     (a)  Any Employee as defined in Section 2 who shall be employed by the
Company on the date his or her participation in the Plan is effective shall be
eligible to participate in the Plan, subject to limitations imposed by Section
423(b) of the Code.

     (b)  Any provisions of the Plan to the contrary notwithstanding, no
Employee shall be granted an option under the Plan (i) if, immediately after the
grant, such Employee (or any other person whose stock would be attributed to
such Employee pursuant to Section 424(d) of the Code) would own stock and/or
hold outstanding options to purchase stock possessing five percent or more of
the total combined voting power or value of all classes of stock of the Company
or of any Subsidiary of the Company, or (ii) which permits his or her rights to
purchase stock under all employee stock purchase plans of the Company and its
Subsidiaries to accrue at a rate which exceeds $25,000 of fair market value of
such stock (determined at the time such option is granted) for each calendar
year in which such option is outstanding at any time.

  4. Offering Periods. The Plan shall be implemented by consecutive 6-month
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Offering Periods with a new Offering Period commencing on February 16 and August
16 of each year; except that the initial Offering Period shall be short Offering
Period commencing on May 20, 1998 and ending on August 14, 1998. (the "Initial
Offering Period"). The Plan shall continue thereafter until terminated in
accordance with Section 20 hereof. Subject to the requirements of Section 19,
the Board shall have the power to change the duration of Offering Periods with
respect to future offerings without stockholder approval if such change is
announced at least 10 days prior to the scheduled beginning of the first
Offering Period to be affected.

  5. Participation.
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     (a)  An eligible Employee may become a participant in the Plan by
completing a subscription agreement authorizing payroll deductions on a form
provided by the Company and filing it with the Company's payroll office at least
10 business days prior to the applicable Offering Date, unless a later time for
filing the subscription agreement is set by the Board for all eligible Employees
with respect to a given offering.

     (b)  Payroll deductions for a participant shall commence on the first
payroll following the Offering Date and shall end on the Exercise Date of the
offering to which such authorization is applicable, unless sooner terminated by
the participant as provided in Section 10.

  6. Payroll Deductions.
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     (a)  At the time a participant files his or her subscription agreement, he
or she shall elect to have payroll deductions made on each payday during the
Offering Period in an amount not exceeding 15% nor less than one percent of his
or her Compensation. The aggregate of such payroll
<PAGE>

deductions during any Offering Period shall not exceed 15% of his or her
aggregate Compensation during said Offering Period.

          (b)  All payroll deductions made by a participant shall be credited to
his or her account under the Plan and will be withheld in whole percentages
only. A participant may not make any additional payments into such account.

          (c)  A participant may discontinue his or her participation in the
Plan as provided in Section 10, or may decrease (but not increase) the rate or
amount of his or her payroll deductions during the Offering Period (within the
limitations of Section 6(a)) by completing and filing with the Company a new
subscription agreement authorizing a decrease in the rate or amount of payroll
deductions; provided, however, that a participant may not decrease the rate or
amount of his or her payroll deductions more than once in any one month. The
change in rate shall be effective 15 days following the Company's receipt of the
new authorization or such shorter period as may be permitted by the Company.
Subject to the limitations of Section 6(a), a participant's subscription
agreement shall remain in effect for successive Offering Periods unless revised
as provided herein or terminated as provided in Section 10.

          (d)  Notwithstanding the foregoing, to the extent necessary to comply
with Section 423(b)(8) of the Code and Section 3(b) herein, a participant's
payroll deductions may be decreased to zero percent by the Administrator at such
time during any Offering Period which is scheduled to end during the current
calendar year that the aggregate of all payroll deductions accumulated with
respect to such Offering Period and any other Offering Period ending within the
same calendar year equal $21,250. Payroll deductions shall recommence at the
rate provided in such participant's subscription agreement at the beginning of
the first Offering Period which is scheduled to end in the following calendar
year, unless terminated by the participant as provided in Section 10.

          (e)  At the time the option is exercised, in whole or in part, or at
the time some or all of the Company's Common Stock issued under the Plan is
disposed of, the participant must make adequate provision for the Company's
federal, state or other tax withholding obligations, if any, which arise upon
the exercise of the option or the dispositions, if any, which arise upon the
exercise of the option or the disposition of the Common Stock. At any time, the
Company may, but will not be obligated to, withhold from the participant's
Compensation the amount necessary for the Company to meet applicable withholding
obligations, including any withholding required to make available to the Company
any tax deductions or benefits attributable to sale or early disposition of
Common Stock by the Employee.

     7.   Grant of Option.
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          (a)  Subject to Sections 7(c) and 7(d) below, on the Offering Date of
each Offering Period, each eligible Employee participating in such Offering
Period shall be granted an option to purchase on each Exercise Date during such
Offering Period (at the per share option price) up to a number of shares of the
Company's Common Stock determined by dividing such Employee's payroll deductions
accumulated prior to such Exercise Date and retained in the Participant's
account as of the Exercise Date by the lower of (i) 85% of the fair market value
of a share of the Company's Common Stock on the Offering Date or (ii) 85% of the
fair market value of a share of the Company's Common Stock on the Exercise Date;
provided, however, that the maximum number of shares an Employee may purchase
during each Offering Period shall be determined at the Offering Date by dividing
$25,000 by the fair market value of a share of the Company's Common Stock on the
Offering Date, and provided further that such purchase shall be subject to the
limitations set forth in Sections 3(b) and 12 hereof. Exercise of each option
during each Offering Period shall occur as provided in Section 8, unless the
participant has withdrawn pursuant to Section 10, and each option shall expire
at midnight on the last day of the applicable Offering Period. Fair market value
of a share of the Company's Common Stock shall be determined as provided in
Section 7(b) herein.
<PAGE>

          (b)  Subject to Sections 7(c) and 7(d) below, the option price per
share of the shares offered in a given Offering Period shall be the lower of:
(i) 85% of the fair market value of a share of the Common Stock of the Company
on the Offering Date; or (ii) 85% of the fair market value of a share of the
Common Stock of the Company on the Exercise Date. The fair market value of the
Company's Common Stock on a given date shall be determined by the Board in its
discretion; provided, however, that where there is a public market for the
Common Stock, the fair market value per share shall be the closing price of the
Common Stock for such date, as reported by the NASDAQ National Market System,
or, in the event the Common Stock is listed on a stock exchange, the fair market
value per share shall be the closing price on such exchange on such date, as
reported in the Wall Street Journal. In the event the Offering Date or the
Exercise Date occurs on a weekend or legal holiday, the fair market value shall
be based on the closing bid price on the next Trading Day.

          (c)  Notwithstanding Sections 7(a) and 7(b) above, (i) each eligible
Employee participating in the Initial Offering Period shall be granted an option
to purchase (at the per share option price) up to a number of shares of the
Company's Common Stock determined by dividing such Employee's payroll deductions
accumulated prior to the Exercise Date and retained in the Participant's account
as of the Exercise Date by 85% of the fair market value of a share of the
Company's Common Stock on the Exercise Date; provided, however, that the maximum
number of shares an Employee may purchase during the Initial Offering Period
shall be determined at the Offering Date by dividing $25,000 by the fair market
value of a share of the Company's Common Stock on the Offering Date, and
provided further that such purchase shall be subject to the limitations set
forth in Sections 3(b) and 12 hereof and (ii) the option price per share of the
shares offered in the Initial Offering Period shall be 85% of the fair market
value of a share of the Common Stock of the Company on the Exercise Date.

          (d)  Notwithstanding anything to the contrary contained herein, in the
event that during any Offering Period the accounting rules relating to
noncompensatory treatment of employee stock purchase plans under section 423 of
the Code change so as to require, in the written opinion of the Company's
independent public accountants, that the Company recognize a compensatory charge
to earnings with respect to options granted during such Offering Period, the
Board may, in its discretion, take any steps necessary to reduce or eliminate
such charge to earnings. Such steps may include (without limitation) (i)
amending the Plan to provide that the Exercise Price for any Offering Period
(including the current Offering Period) shall be equal to 85% of the fair market
value of a share of the Common Stock of the Company on the Exercise Date only or
(ii) immediately terminating the Offering Period and returning all payroll
deductions withheld to participants prior to the Exercise Date. The Board will
advise participants of any accounting-related amendment that affects pricing no
less than 5 business days prior to the Exercise Date of the affected Offering
Period. No prior notice will be required in the event of an accounting-related
termination of the Offering Period provided that payroll deductions are returned
to the participant as promptly as practicable after the termination.

     8.   Exercise of Option.  Unless a participant withdraws from the Plan as
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provided in Section 10, his or her option for the purchase of shares will be
exercised automatically on the Exercise Date, and the maximum number of full
shares subject to option shall be purchased for such participant at the
applicable option price with the accumulated payroll deductions in his or her
account.  No fractional shares will be purchased and any amount remaining in the
participant's account after an Exercise Date shall be held in the account until
the Exercise Date of the next Offering Period, unless the Offering Period has
been oversubscribed or the Plan has terminated with such Exercise Date, in which
case such amount shall be refunded to the participant.  During a participant's
lifetime, a participant's option to purchase shares hereunder is exercisable
only by him or her.

     9.   Delivery.  As promptly as practicable after the Exercise Date, the
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Company shall arrange the delivery to each participant, as appropriate, of a
certificate representing the shares purchased upon exercise of his or her
option.  Any cash remaining to the credit of a participant's account under the
Plan after a purchase by him or her of shares at the termination of each
Offering Period which is insufficient to
<PAGE>

purchase a full share of Common Stock of the Company shall be applied to the
participant's account for the next Offering Period.

     10.  Withdrawal; Termination of Employment.
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          (a)  A participant may withdraw all but not less than all the payroll
deductions credited to his or her account and not yet used to exercise his or
her option under the Plan at any time by giving written notice to the Company
pursuant to a form to be provided by the Company. All of the participant's
payroll deductions credited to his or her account will be paid to such
participant as promptly as practicable after receipt of notice of withdrawal and
such participant's remaining option or options for the Offering Period will be
automatically terminated, and no further payroll deductions for the purchase of
shares will be made during the Offering Period. If a participant withdraws from
an Offering Period, payroll deductions will not resume at the beginning of the
succeeding Offering Period unless the participant delivers to the Company a new
subscription agreement.

          (b)  Upon a participant's ceasing to be an Employee prior to an
Exercise Date for any reason, including retirement or death, or upon termination
of a participant's employment relationship (as described in Section 2(g)), the
payroll deductions credited to such participant's account during the Offering
Period but not yet used to exercise the option will be returned to such
participant or, in the case of his or her death, to the person or persons
entitled thereto under Section 14, and such participant's remaining option or
options will be automatically terminated.

          (c)  In the event an Employee fails to remain an Employee of the
Company for at least 20 hours per week during an Offering Period in which the
Employee is a participant, he or she will be deemed to have elected to withdraw
from the Plan and the payroll deductions credited to his or her account will be
returned to such participant and such participant's remaining option or options
terminated.

          (d)  A participant's withdrawal from an Offering Period will not have
any effect upon his or her eligibility to participate in any similar plan which
may hereafter be adopted by the Company or in succeeding Offering Periods which
commence after the participant withdraws.

     11.  Interest.  No interest shall accrue on the payroll deductions of a
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participant in the Plan.

     12.  Stock.
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          (a) Subject to Section 18 of the Plan, the maximum number of Shares
reserved and available for issuance pursuant to the Plan is 2,000,000. If any
Shares that have been optioned under the Plan cease to be subject to an option
(other than through exercise of the option), or if any option granted hereunder
is forfeited, the Shares that were subject to such option shall again be
available for distribution in connection with future grants under the Plan.
Notwithstanding the previous sentence, if Shares subject to an option are used
for tax withholding, only the net number of Shares issued to the participant in
the transaction shall be considered to be "issued" under the Plan, and the
remaining Shares that were subject to such option shall again be available for
distribution in connection with future option grants under the Plan.

     If on a given Exercise Date the number of shares with respect to which
options are to be exercised exceeds the number of shares then available under
the Plan (after deduction of all shares for which options have been exercised or
are then outstanding), the Board shall make a pro rata allocation of the shares
remaining available for option grant in as uniform a manner as shall be
practicable or, subject to the restrictions of Section 423 of the Code, take
such other steps to reallocate Shares as it determines shall be equitable. The
Company shall give written notice of such reduction or reallocation to each
Employee affected thereby and shall similarly reduce the rate of payroll
deductions, if necessary.
<PAGE>

          (b)  The participant will have no interest or voting right in shares
covered by his or her option until such option has been exercised.

          (c)  Shares to be delivered to a participant under the Plan will be
registered in the name of the participant or in the name of the participant and
his or her spouse.

     13.  Administration.  The Plan shall be administered by the Board of
          --------------
Directors of the Company or a committee appointed by the Board.  The Board or
its committee shall have full and exclusive discretionary authority to construe,
interpret and apply the terms of the Plan, to determine eligibility and to
adjudicate all disputed claims filed under the Plan.  Every finding, decision
and determination made by the Board or its committee shall, to the full extent
permitted by law, be final and binding upon all parties.  Members of the Board
who are eligible Employees are permitted to participate in the Plan.

     14.  Designation of Beneficiary.
          --------------------------

          (a)  A participant may file a written designation of a beneficiary who
is to receive any shares and cash, if any, from the participant's account under
the Plan in the event of such participant's death subsequent to the end of the
Offering Period but prior to delivery to him or her of such shares and cash. In
addition, a participant may file a written designation of a beneficiary who is
to receive any cash from the participant's account under the Plan in the event
of such participant's death prior to an Exercise Date.

          (b)  Such designation of beneficiary may be changed by the participant
at any time by written notice. In the event of the death of a participant and in
the absence of a beneficiary validly designated under the Plan who is living at
the time of such participant's death, the Company shall deliver such shares
and/or cash to the executor or administrator of the estate of the participant,
or if no such executor or administrator has been appointed (to the knowledge of
the Company), the Company, in its discretion, may deliver such shares and/or
cash to the spouse or to any one or more dependents or relatives of the
participant, or if no spouse, dependent or relative is known to the Company,
then to such other person as the Company may designate.

     15.  Transferability. Neither payroll deductions credited to a
          ---------------
participant's account nor any rights with regard to the exercise of an option or
to receive shares under the Plan may be assigned, transferred, pledged or
otherwise disposed of in any way (other than by will, the laws of descent and
distribution or as provided in Section 14 hereof) by the participant. Any such
attempt at assignment, transfer, pledge or other disposition shall be without
effect, except that the Company may treat such act as an election to withdraw
funds from an Offering Period in accordance with Section 10.

     16.  Use of Funds.  All payroll deductions received or held by the Company
          ------------
under the Plan may be used by the Company for any corporate purpose, and the
Company shall not be obligated to segregate such payroll deductions.

     17.  Reports.  Individual accounts will be maintained for each participant
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in the Plan.  Statements of account will be given to participating Employees
annually, which statements will set forth the amounts of payroll deductions, the
per share purchase price, the number of shares purchased and the remaining cash
balance, if any.

     18.  Adjustments Upon Changes in Capitalization.  Subject to any required
          ------------------------------------------
action by the stockholders of the Company, the number of shares of Common Stock
covered by each option under the Plan which has not yet been exercised and the
number of shares of Common Stock which have been authorized for issuance under
the Plan but have not yet been placed under option (collectively, the
"Reserves") as well as the price per share of Common Stock covered by each
option under the Plan which has not yet been exercised, shall be proportionately
adjusted for any increase or decrease in the number of issued shares of Common
Stock resulting from a stock split, reverse stock split, stock dividend,
combination
<PAGE>

or reclassification of the Common Stock, or any other increase or decrease in
the number of shares of Common Stock effected without receipt of any conversion
of any convertible securities of the Company shall not be deemed to have been
"effected without receipt of consideration." Such adjustment shall be made by
the Board, whose determination in that respect shall be final, binding and
conclusive. Except as expressly provided herein, no issue by the Company of
shares of stock of any class, or securities convertible into shares of stock of
any class, shall affect, and no adjustment by reason thereof shall be made with
respect to, the number or price of shares of Common Stock subject to an option.

     In the event of the proposed dissolution or liquidation of the Company, the
Offering Period will terminate immediately prior to the consummation of such
proposed action, unless otherwise provided by the Board.  In the event of a
proposed sale of all or substantially all of the assets of the Company, or the
merger of the Company with or into another corporation, each option under the
Plan shall be assumed or an equivalent option shall be substituted by such
successor corporation or a parent or subsidiary of such successor corporation,
unless the Board determines, in the exercise of its sole discretion and in lieu
of such assumption or substitution, to shorten the Offering Period then in
progress by setting a new Exercise Date (the "New Exercise Date").  If the Board
shortens the Offering Period then in progress in lieu of assumption or
substitution in the event of a merger or sale of assets, the Board shall notify
each participant in writing, at least  5 business days prior to the New Exercise
Date, that the Exercise Date for his or her option has been changed to the New
Exercise Date and that his or her option has been changed to the New Exercise
Date and that his or her option will be exercised automatically on the New
Exercise Date, unless prior to such date he or she has withdrawn from the
Offering Period as provided in Section 10.  For purposes of this paragraph, an
option granted under the Plan shall be deemed to be assumed if, following the
sale of assets or merger the option confers the right to purchase, for each
share of option stock subject to the option immediately prior to the sale of
assets or merger the consideration (whether stock, cash or other securities or
property) received in the sale of assets or merger by holders of Common Stock
for each share of Common Stock held on the effective date of the transaction
(and if such holders were offered a choice of consideration, the type of
consideration chosen by the holders of a majority of the outstanding shares of
Common Stock); provided, however, that if such consideration received in the
sale of assets or merger was not solely common stock of the successor
corporation or its parent (as defined in Section 424(e) of the Code), the Board
may, with the consent of the successor corporation and the participant, provide
for the consideration to be received upon exercise of the option to be solely
common stock of the successor corporation or its parent equal in fair market
value to the per share consideration received by holders of Common Stock in the
sale of assets or merger.

     The Board may, if it so determines in the exercise of its sole discretion,
also make provision for adjusting the reserves, as well as the price per share
of Common Stock covered by each outstanding option, in the event that the
Company effects one or more reorganizations, recapitalizations, rights offerings
or other increases or reductions of shares of its outstanding Common Stock, and
in the event of the Company being consolidated with or merged into any other
corporation.

     19.  Amendment or Termination.
          ------------------------

          (a)  The Board may at any time and for any reason terminate or amend
the Plan. Except as provided in Section 7(c) and Section 18, no such termination
can affect options previously granted, provided that the Plan may be terminated
by the Board on any Exercise Date if the Board determines that the termination
of the Plan is in the best interests of The Company and its stockholders. Except
as provided in Section 7(c) and Section 18 no amendment may make any change in
any option theretofore granted which adversely affects the rights of any
participant. To the extent necessary to comply with Section 423 of the Code (or
any successor rule or provision or any other applicable law or regulation), the
Company shall obtain stockholder approval in such a manner and to such a degree
as required.

          (b)  Without stockholder consent and without regard to whether any
participant rights may be considered to have been "adversely affected," the
Board (or its committee) shall be entitled to
<PAGE>

change the Offering Periods, limit the frequency and/or number of changes in the
amount withheld during an Offering Period, establish the exchange ratio
applicable to amounts withheld in a currency other than U.S. dollars, permit
payroll withholding in excess of the amount designated by a participant in order
to adjust for delays or mistakes in the Company's processing of properly
completed withholding elections, establish reasonable waiting and adjustment
periods and/or accounting and crediting procedures to ensure that amounts
applied toward the purchase of Common Stock for each participant properly
correspond with amounts withheld from the participant's Compensation, and
establish such other limitations or procedures as the Board (or its committee)
determines in its sole discretion advisable which are consistent with the Plan.

     20.  Notices. All notices or other communications by a participant to the
          -------
Company under or in connection with the Plan shall be deemed to have been duly
given when received in the form specified by the Company at the location, or by
the person, designated by the Company for the receipt thereof. All notices or
other communications by the Company to a participant under or in connection with
the Plan shall be deemed to have been duly given when mailed to the participant
at the last address provided by the participant to the Company.

     21.  Conditions Upon Issuance of Shares. Shares shall not be issued with
          ----------------------------------
respect to an option unless the exercise of such option and the issuance and
delivery of such shares pursuant thereto shall comply with all applicable
provisions of law, domestic or foreign, including, without limitation, the
Securities Act of 1933, as amended, the Securities Exchange Act of 1934, as
amended, the rules and regulations promulgated thereunder, and the requirements
of any stock exchange upon which the shares may then be listed, and shall be
further subject to the approval of counsel for the Company with respect to such
compliance.

     As a condition to the exercise of an option, the Company may require the
person exercising such option to represent and warrant at the time of any such
exercise that the shares are being purchased only for investment and without any
present intention to sell or distribute such shares if, in the opinion of
counsel for the Company, such a representation is required by any of the
aforementioned applicable provisions of law.

     21.  Term of Plan. The Plan shall become effective on May 20, 1998 and
          ------------
terminate on August 16, 2008 unless sooner terminated under Section 19.
<PAGE>

                                   EXHIBIT A
                                   ---------

                        MERCURY INTERACTIVE CORPORATION

                       1998 EMPLOYEE STOCK PURCHASE PLAN

                            SUBSCRIPTION AGREEMENT


[_]  Original Application                                         Offering Date:


[_]  Decrease in Payroll Deduction Rate


[_]  Change of Beneficiary


1.   ____________________________ hereby elects to participate in the Mercury
     Interactive Corporation 1998 Employee Stock Purchase Plan (the "Stock
     Purchase Plan") and subscribes to purchase shares of the Company's Common
     Stock in accordance with this Subscription Agreement and the Stock Purchase
     Plan.

2.   I hereby authorize payroll deductions from each paycheck in the amount of
     __% of my Compensation on each payday (not to be less than one percent and
     not to exceed 15%) during the Offering Period in accordance with the Stock
     Purchase Plan. (Please note that no fractional percentages are permitted).
     Such deductions are to continue for succeeding Offering Periods under the
     Stock Purchase Plan until I give written instructions for a decrease in or
     termination of such deductions.

3.   I understand that said payroll deductions shall be accumulated for the
     purchase of shares of Common Stock at the applicable purchase price
     determined in accordance with the Stock Purchase Plan. I further
     understand that, except as otherwise set forth in the Stock Purchase Plan,
     shares will be purchased for me automatically on each Exercise Date unless
     I otherwise withdraw from the Stock Purchase Plan by giving written notice
     to the Company for such purpose and any amounts not used to puchase shares
     will be applied to the next Offering Period.

4.   Shares purchased for me under the Stock Purchase Plan should be issued in
     the name(s) of: ___________________________________________________________
     ___________________________________________________________________________
     ___________________________________________________________________________

5.   I acknowledge that, under the Internal Revenue Code, there are special tax
     "holding period" rules that govern the tax consequences of buying and
     selling shares under the Stock Purchase Plan. I understand that if I
     dispose of shares purchased under the Plan within two years of the Offering
     Date (i.e., the first day of the Offering Period) or within one year of the
     Exercise Date (i.e., the date the shares are purchased), I will be treated
     for federal income tax purposes as having received ordinary income at the
     time of the sale equal to the difference between my purchase price and the
     market value of the stock on the Exercise Date. Any amount in excess of
                               --------------------
     that difference will be treated as capital gain.  I hereby agree to notify
     the Company in writing within 30 days after the date of any such
     disposition.

     I further understand that if I hold the shares for both the two-year and
     one-year holding periods described above, at the time I dispose of the
     shares I will be treated for federal income tax purposes as having received
     ordinary income in an amount equal only to the lesser of (1) the difference
     between my purchase price and the market value of the stock on the Offering
                                                                 ---------------
     Date or (2) the
     ----
<PAGE>

     difference between my purchase price and the actual sale price for my
     stock. Any additional gain I receive on the sale will be treated as capital
     gain.

6.   I have received a copy of the Company's most recent prospectus which
     describes the Stock Purchase Plan and a copy of the complete "Mercury
     Interactive Corporation 1998 Employee Stock Purchase Plan." I understand
     that my participation in the Stock Purchase Plan is in all respects subject
     to the terms of the Plan.

7.   I hereby agree to be bound by the terms of the Stock Purchase Plan. The
     effectiveness of this Subscription Agreement is dependent upon my
     eligibility to participate in the Stock Purchase Plan.

8.   In the event of my death, I hereby designate the following as my
     beneficiary(ies) to receive all payments and shares due me under the Stock
     Purchase Plan:

NAME (Please print): ___________________________________________________________
                     (First)                (Middle)                      (Last)

_______________________   ______________________________________________________
Relationship
                          ______________________________________________________
                          (Address)


NAME (Please print): ___________________________________________________________
                     (First)                (Middle)                      (Last)

_______________________   ______________________________________________________
Relationship
                          ______________________________________________________
                          (Address)

_______________________   ______________________________________________________
NAME (Please print):      (First)           (Middle)                      (Last)

_______________________   ______________________________________________________
Relationship
                          ______________________________________________________
                          (Address)


Employee's Social Security Number: _____________________________________________

Employee's Address:            _________________________________________________

                               _________________________________________________

                               _________________________________________________
<PAGE>

     I UNDERSTAND THAT THIS SUBSCRIPTION AGREEMENT SHALL REMAIN IN EFFECT
THROUGHOUT SUCCESSIVE OFFERING PERIODS UNLESS TERMINATED BY ME.


Dated:_________________             ____________________________________________
                                    Signature of Employee
<PAGE>

                                   EXHIBIT B
                                   ---------

                        MERCURY INTERACTIVE CORPORATION

                       1998 EMPLOYEE STOCK PURCHASE PLAN

                             NOTICE OF WITHDRAWAL


     The undersigned participant in the Offering Period of the Mercury
Interactive Corporation 1998 Employee Stock Purchase Plan which began on
________ __, 199_ (the "Offering Date") hereby notifies the Company that he or
she hereby withdraws from the Offering Period. He or she hereby directs the
Company to pay to the undersigned as promptly as possible all the payroll
deductions credited to his or her account with respect to such Offering Period.
The undersigned understands and agrees that his or her remaining option or
options for such Offering Period will be automatically terminated. The
undersigned understands further that no further payroll deductions will be made
for the purchase of shares in the current Offering Period and the undersigned
shall be eligible to participate in succeeding Offering Periods only by
delivering to the Company a new Subscription Agreement.

                                    Name and Address of Participant

                                    ____________________________________________

                                    ____________________________________________

                                    ____________________________________________

                                    Signature


                                    ____________________________________________

                                    Date: ______________________________________
<PAGE>

                                   EXHIBIT C
                                   ---------

                        MERCURY INTERACTIVE CORPORATION

                       1998 EMPLOYEE STOCK PURCHASE PLAN

                      NOTICE OF SALE OR OTHER DISPOSITION


To:  Mercury Interactive Corporation
     ______________________________________
     ______________________________________
     ______________________________________

     Attn: _______________________


     This notice is to inform the Company of sales or other dispositions of
stock acquired under the 1998 Employee Stock Purchase Plan, so that the Company
can fulfill its tax reporting obligations. This form must be completed and
submitted to the Company whenever you sell stock acquired under the Plan, even
if you no longer are employed by the Company. If you need assistance in
completing this form, contact the Human Resources Department.

1.   Employee Name: ____________________________________________________________

2.   Number of Shares Sold or Disposed of: _____________________________________

3.   Date(s) these Shares were purchased under the Plan: _______________________

     ___________________________________________________________________________

4.   Date of Sale or other Disposition: ________________________________________

5.   Type of Disposition:  Sale __  Gift __  Other (describe) __

     ___________________________________________________________________________

6.   Stock Price per Share at Sale or Disposition: $ ___________________________

7.   Amount Received on Sale or Disposition: $ _________________________________



                                        ________________________________________
                                               Employee Signature