Exhibit 10.2

FIFTH AMENDMENT OF CREDIT AGREEMENT

THIS FIFTH AMENDMENT OF CREDIT AGREEMENT (hereinafter referred to as the
"Amendment"), dated effective as of August 31, 2017, is made and entered into by
and between NATURAL GAS SERVICES GROUP, INC., a Colorado corporation (the
"Borrower"), and JPMORGAN CHASE BANK, N.A., a national banking association (the
"Lender").

RECITALS:

1.The Borrower and the Lender have entered into a Credit Agreement dated as of
December 10, 2010, as previously amended pursuant to the terms of that certain
First Amendment of Credit Agreement dated December 31, 2011, executed by and
between the Borrower and the Lender, that certain Second Amendment of Credit
Agreement dated December 30, 2013, executed by and between the Borrower and the
Lender, that certain Third Amendment of Credit Agreement dated November 19,
2014, executed by and between the Borrower and the Lender, and that certain
Fourth Amendment of Credit Agreement dated December 31, 2015, executed by and
between the Borrower and the Lender (said Credit Agreement, as previously
amended, shall hereinafter be collectively referred to as the "Credit
Agreement").

2.In connection with a further extension of the Maturity Date under the Credit
Agreement, the Lender and the Borrower desire to modify, amend and supplement
the Credit Agreement in certain respects.

AGREEMENTS:

NOW, THEREFORE, in consideration of the premises and the mutual agreements,
representations and warranties herein set forth, and for other good and valuable
consideration, the receipt and sufficiency of which are acknowledged, the
Borrower and the Lender do hereby agree as follows:-
          
Section 1. Amendment of “Maturity Date” and “Note” Definitions. The definitions
for “Maturity Date” and “Note” in Section 1.01 of the Credit Agreement are
hereby amended and restated in their entirety to hereafter read as follows:

Maturity Date means the earlier to occur of (a) December 31, 2020, (b) any date
that the Commitment is terminated in full by Borrower pursuant to Section
2.01(b) hereof, and (c) any date the Maturity Date is accelerated or the
Commitment is terminated by Lender pursuant to Section 7.02 hereof.

Note means the promissory note dated August 31, 2017, executed by Borrower
payable to the order of Lender in the face amount of $30,000,000.00, and any and
all renewals, extensions, modifications, increases, rearrangements and/or
replacements thereof.

Section 2. Modification of Other Existing Definitions. The definitions for
“Adjusted One Month LIBOR Rate”, “Change in Law”, “LIBOR Rate” and “Obligations”
in Section 1.01 of the Credit Agreement are hereby amended and restated in their
entirety to hereafter read as follows:

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Adjusted One Month LIBOR Rate means, for any day, an interest rate per annum
equal to the sum of (i) 2.50% per annum plus (ii) the Adjusted LIBOR Rate for a
one-month interest period on such day (or if such day is not a Business Day, the
immediately preceding Business Day); provided that, for the avoidance of doubt,
the Adjusted LIBOR Rate for any day shall be based on the LIBO Screen Rate at
approximately 11:00 a.m. London time on such day.

Change in Law means the occurrence after the date of this Agreement of any of
the following: (a) the adoption of or taking effect of any law, rule, regulation
or treaty, (b) any change in any law, rule, regulation or treaty or in the
administration, interpretation or application thereof by any Governmental
Authority or (c) compliance by the Lender (or, for purposes of Section 2.06(b),
by any lending office of the Lender or by the Lender’s holding company, if any)
with any request, guideline, requirement or directive (whether or not having the
force of law) of any Governmental Authority made or issued after the date of
this Agreement; provided that, notwithstanding anything herein to the contrary,
(x) the Dodd-Frank Wall Street Reform and Consumer Protection Act and all
requests, rules, guidelines, requirements or directives thereunder or issued in
connection therewith or in the implementation thereof, and (y) all requests,
rules, guidelines, requirements or directives promulgated by the Bank for
International Settlements, the Basel Committee on Banking Supervision (or any
successor or similar authority) or the U.S. or foreign regulatory authorities,
in each case pursuant to Basel III, shall in each case be deemed to be a “Change
in Law”, regardless of the date enacted, adopted, issued or implemented.

LIBOR Rate means, with respect to any LIBOR Borrowing for any applicable
Interest Period or for any CBFR Borrowing, the LIBO Screen Rate at approximately
11:00 a.m., London time, two (2) Business Days prior to the commencement of such
Interest Period; provided that, if the LIBO Screen Rate shall not be available
at such time for a period equal in length to such Interest Period (an “Impacted
Interest Period”), then the LIBO Rate shall be the Interpolated Rate at such
time.

Obligations means (a) the Indebtedness evidenced by the Note and other sums now
or hereafter payable to Lender by Borrower or any other Obligor under any of the
Credit Documents, including all payment and other obligations and liabilities of
Borrower, contingent or otherwise, whether now or hereafter arising under any
Rate Management Transaction, together with performance of all other payment
obligations, liabilities and Indebtedness of Borrower to Lender under any one or
more of the Credit Documents, including all fees, costs, expenses and indemnity
obligations under this Agreement and all other Credit Documents, and (b) the
Banking Service Obligations; provided, however, that the definition of
“Obligations” shall not create any guarantee by any Guarantor of (or grant of
security interest by any Guarantor to support, as applicable) any Excluded Swap
Obligations of such Guarantor for purposes of determining any obligations of any
Guarantor.

Section 3.    Addition of New Definitions. The following new definitions are
hereby added to Section 1.01 of the Credit Agreement:

Anti-Corruption Laws means all laws, rules, and regulations of any jurisdiction
applicable to Borrower or any Affiliate of Borrower from time to time concerning
or relating to bribery or corruption.

“Banking Services” means each and any of the following bank services provided to
Borrower or any other Obligor by Lender or any of its Affiliates: (a) credit
cards for commercial customers (including, without limitation, “commercial
credit cards” and purchasing cards), (b) stored value cards, (c) merchant
processing services, and (d) treasury management services (including, without
limitation, controlled disbursement, automated clearinghouse transactions,
return items, any direct

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debit scheme or arrangement, overdrafts and interstate depository network
services).

“Banking Services Obligations” means any and all obligations of Borrower or any
other Obligor, whether absolute or contingent and howsoever and whensoever
created, arising, evidenced or acquired (including all renewals, extensions and
modifications thereof and substitutions therefor) in connection with Banking
Services.

Commodity Exchange Act means the Commodity Exchange Act (7 U.S.C. § 1 et seq.),
as amended from time to time, and any successor statute.

Connection Income Taxes means Other Connection Taxes that are imposed on or
measured by net income (however denominated) or that are franchise Taxes or
branch profits Taxes.

ECP means an “eligible contract participant” as defined in Section 1(a)(18) of
the Commodity Exchange Act or any regulations promulgated thereunder and the
applicable rules issued by the Commodity Futures Trading Commission and/or the
SEC.

Electronic System means any electronic system, including e-mail, e-fax, web
portal access for Borrower, Intralinks®, ClearPar®, Debt Domain, Syndtrak and
any other Internet or extranet-based site, whether such electronic system is
owned, operated or hosted by Lender and any of its respective Affiliates or any
other Person, providing for access to data protected by passcodes or other
security system.

Excluded Swap Obligation means, with respect to any Guarantor, any Swap
Obligation if, and to the extent that, all or a portion of the Guaranty of such
Guarantor of, or the grant by such Guarantor of a security interest to secure,
such Swap Obligation (or any Guarantee thereof) is or becomes illegal under the
Commodity Exchange Act or any rule, regulation or order of the Commodity Futures
Trading Commission (or the application or official interpretation of any
thereof) by virtue of such Guarantor’s failure for any reason to constitute an
ECP at the time the Guaranty of such Guarantor or the grant of such security
interest becomes or would become effective with respect to such Swap Obligation.
If a Swap Obligation arises under a master agreement governing more than one
swap, such exclusion shall apply only to the portion of such Swap Obligation
that is attributable to swaps for which such Guaranty or security interest is or
becomes illegal.

Excluded Taxes means any of the following Taxes imposed on or with respect to
the Lender or required to be withheld or deducted from a payment to Lender: (a)
Taxes imposed on or measured by net income (however denominated), franchise
Taxes, and branch profits Taxes, in each case, (i) imposed as a result of Lender
being organized under the laws of, or having its principal office or its
applicable lending office located in, the jurisdiction imposing such Tax (or any
political subdivision thereof) or (ii) that are Other Connection Taxes, and (b)
any U.S. federal withholding Taxes imposed under FATCA.

FATCA means Sections 1471 through 1474 of the Code as of the date of this
Agreement (or any amended or successor version that is substantively comparable
and not materially more onerous to comply with), any current or future
regulations or official interpretations thereof and any agreement entered into
pursuant to Section 1471(b)(1) of the Internal Revenue Code.

Impacted Interest Period has the meaning assigned to such term in the definition
of “LIBOR Rate”.

Indemnified Taxes means (a) Taxes, other than Excluded Taxes, imposed on or with
respect

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to any payment made by or on account of any obligation of any Obligor under any
Credit Document and (b) to the extent not otherwise described in the foregoing
clause (a), Other Taxes.

Interpolated Rate means, at any time, for any Interest Period, the rate per
annum (rounded to the same number of decimal places as the LIBO Screen Rate)
determined by Lender (which determination shall be conclusive and binding absent
manifest error) to be equal to the rate that results from interpolating on a
linear basis between: (a) the LIBO Screen Rate for the longest period (for which
the LIBO Screen Rate is available) that is shorter than the Impacted Interest
Period and (b) the LIBO Screen Rate for the shortest period (for which the LIBO
Screen Rate is available) that exceeds the Impacted Interest Period, in each
case, at such time.

LIBO Screen Rate means, for any day and time, with respect to any LIBOR
Borrowing for any Interest Period or for any CBFR Borrowing, the London
interbank offered rate as administered by ICE Benchmark Administration (or any
other Person that takes over the administration of such rate for Dollars) for a
period equal in length to such Interest Period as displayed on such day and time
on pages LIBOR01 or LIBOR02 of the Reuters screen that displays such rate (or,
in the event such rate does not appear on a Reuters page or screen, on any
successor or substitute page on such screen that displays such rate, or on the
appropriate page of such other information service that publishes such rate from
time to time as selected by Lender in its reasonable discretion); provided that
if the LIBO Screen Rate shall be less than zero, such rate shall be deemed to be
zero for the purposes of this Agreement.

Other Connection Taxes means, with respect to Lender, Taxes imposed as a result
of a present or former connection between Lender and the jurisdiction imposing
such Taxes (other than a connection arising from Lender having executed,
delivered, become a party to, performed its obligations under, received payments
under, received or perfected a security interest under, engaged in any other
transaction pursuant to, or enforced, any Credit Document), or sold or assigned
an interest in any Loan, Letter of Credit, or any Credit Document.

Other Taxes means all present or future stamp, court or documentary, intangible,
recording, filing or similar Taxes that arise from any payment made under, from
the execution, delivery, performance, enforcement or registration of, from the
receipt or perfection of a security interest under, or otherwise with respect
to, any Credit Document, except any such Taxes that are Other Connection Taxes
imposed with respect to an assignment.

Qualified ECP Guarantor means, in respect of any Swap Obligation, each Obligor
that has total assets exceeding $10,000,000 at the time the relevant Guaranty or
grant of the relevant security interest becomes or would become effective with
respect to such Swap Obligation or such other person as constitutes an “eligible
contract participant” under the Commodity Exchange Act or any regulations
promulgated thereunder and can cause another person to qualify as an “eligible
contract participant” at such time by entering into a keepwell under Section
1a(18)(A)(v)(II) of the Commodity Exchange Act.

Sanctioned Country means, at any time, a country or territory which is the
subject or target of any Sanctions (at the time of this Agreement, Crimea, Cuba,
Iran, North Korea, Sudan and Syria).

Sanctioned Person means, at any time, (a) any Person listed in any
Sanctions-related list of designated Persons maintained by the Office of Foreign
Assets Control of the U.S. Department of the Treasury or the U.S. Department of
State, (b) any Person operating, organized or resident in a Sanctioned Country
or (c) any Person owned or controlled by any such Person or Persons described

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in the foregoing clauses (a) or (b).

Sanctions means all economic or financial sanctions or trade embargoes imposed,
administered or enforced from time to time by the U.S. government, including
those administered by the Office of Foreign Assets Control of the U.S.
Department of the Treasury or the U.S. Department of State.

Swap Obligation means, with respect to any Guarantor, any obligation to pay or
perform under any agreement, contract or transaction that constitutes a "swap"
within the meaning of section 1a(47) of the Commodity Exchange Act or any rules
or regulations promulgated thereunder.

Taxes means any and all present or future taxes, levies, imposts, duties,
deductions, withholdings (including backup withholding), value added taxes, or
any other goods and services, use or sales taxes, assessments, fees or other
charges imposed by any Governmental Authority, including any interest, additions
to tax or penalties applicable thereto.

Section 4.    Modification of Special Provisions Applicable to LIBOR Borrowings.
Section 2.05 of the Credit Agreement is hereby amended and restated in its
entirety to hereafter read as follows:

(a)    If prior to the commencement of any Interest Period for a LIBOR
Borrowing:

(i)     Lender determines (which determination shall be conclusive and binding
absent manifest error) that adequate and reasonable means do not exist for
ascertaining (including, without limitation, by means of an Interpolated Rate)
the Adjusted LIBO Rate or the LIBO Rate, as applicable, for such Interest
Period; or

(ii)     Lender determines the Adjusted LIBO Rate or the LIBO Rate, as
applicable, for such Interest Period will not adequately and fairly reflect the
cost to Lender of making or maintaining its Loan included in such Borrowing for
such Interest Period;

then Lender shall give notice thereof to the Borrower by telephone, fax or
through Electronic System as provided in Section 8.08 as promptly as practicable
thereafter and, until Lender notifies the Borrower that the circumstances giving
rise to such notice no longer exist, (x) any Rate Selection Notice that requests
the conversion of any Borrowing to, or continuation of any Borrowing as, a LIBOR
Borrowing shall be ineffective and any such LIBOR Borrowing shall be repaid on
the last day of the then current Interest Period applicable thereto, and (y) if
any Rate Selection Notice requests a LIBOR Borrowing, such Borrowing shall be
made as a CBFR Borrowing.

(b)    Borrower hereby agrees to indemnify Lender against and hold Lender
harmless from any actual loss or expense that Lender may sustain or incur as a
consequence of (i) failure by Borrower to timely convert or borrow any LIBOR
Borrowing after Borrower has given a notice requesting the same in accordance
with the provisions of this Agreement, (ii) failure by Borrower to make any
prepayment after Borrower has given a notice thereof in accordance with the
provisions of this Agreement or (iii) the making of a payment or prepayment of
any LIBOR Borrowing, or the conversion of any LIBOR Borrowing, on a day that is
not the last day of an Interest Period with respect thereto, including without
limitation, in each case, any such loss or expense arising from the liquidation
or reemployment of funds obtained by Lender or from fees payable to terminate
the deposits from which such funds were obtained.

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(c)    If Borrower requests quotes of the Adjusted LIBOR Rate for different
Interest Periods being considered for election by Borrower, Lender will use
reasonable efforts to provide such quotes to Borrower promptly. However, all
such quotes provided shall be representative only and shall not be binding on
Lender, nor shall they be determinative, directly or indirectly, of any Adjusted
LIBOR Rate or any component of any such rate, nor will Borrower's failure to
receive or Lender's failure to provide any requested quote or quotes either (1)
excuse or extend the time for performance of any obligation of Borrower or for
the exercise of any right, option or election of Borrower or (2) impose any duty
or liability on Lender. If Borrower requests a list of the Business Days in any
calendar month, Lender will use reasonable efforts to provide such list
promptly. However, any such list provided shall be understood to identify only
those days which Lender believes in good faith at the time such list is prepared
will be the Business Days for such month. Lender shall not have any liability
for any failure to provide, delay in providing, error or mistake in or omission
from, any such quote or list.
(d)    With respect to Lender having a LIBOR Lending Office which differs from
its Domestic Lending Office, all Loans that are part of LIBOR Borrowings
advanced by Lender's LIBOR Lending Office shall be deemed to have been made by
Lender and the obligation of Borrower to repay such Loans shall nevertheless be
to Lender and shall be deemed held by Lender for the account of Lender's LIBOR
Lending Office.
Section 5.    Modification of Increased Costs Provisions. Section 2.06 of the
Credit Agreement is hereby amended and restated in its entirety to hereafter
read as follows:

Section 2.06     Increased Costs.

(a)    If Lender reasonably determines that any Change in Law shall:

(i) impose, modify or deem applicable any reserve, special deposit, liquidity or
similar requirement (including any compulsory loan requirement, insurance charge
or other assessment) against assets of, deposits with or for the account of, or
credit extended by, Lender (except any such reserve requirement reflected in the
Adjusted LIBOR Rate);

(ii) impose on Lender or the London interbank market any other condition, cost
or expense (other than Taxes) affecting this Agreement or any Loans made
hereunder; or

(iii) subject Lender to any Taxes (other than (A) Indemnified Taxes, (B) Taxes
described in clause (b) of the definition of Excluded Taxes and (C) Connection
Income Taxes) on its loans, loan principal, letters of credit, commitments, or
other obligations, or its deposits, reserves, other liabilities or capital
attributable thereto,

and the result of any of the foregoing shall be to increase the cost to Lender
of making, continuing, converting into or maintaining any Loan (or of
maintaining its obligation to make any such Loan) or to reduce the amount of any
sum received or receivable by Lender hereunder (whether of principal, interest
or otherwise), then Borrower will pay to Lender such additional amount or
amounts as will compensate Lender for such additional costs incurred or
reduction suffered.

(b)    If Lender reasonably determines that any Change in Law regarding capital
or liquidity requirements has or would have the effect of reducing the rate of
return on Lender’s capital or on the capital of Lender’s holding company as a
consequence of this Agreement, the Commitment of or the Loans made by Lender to
a level below that which Lender or Lender’s holding company could have

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achieved but for such Change in Law (taking into consideration Lender’s policies
and the policies of Lender’s holding company with respect to capital adequacy
and liquidity), then from time to time Borrower will pay to Lender such
additional amount or amounts as will compensate Lender or Lender’s holding
company for any such reduction suffered; provided, however, that notwithstanding
the foregoing, if Borrower (i) fully pays all outstanding Obligations, (ii) pays
to Lender, in immediately available funds, an amount equal to 105% of the then
aggregate amount available for drawings under all outstanding Letters of Credit,
if any (which funds shall be held by Lender as Cover for said Letters of
Credit), and (iii) irrevocably terminates the Commitment in writing delivered to
Lender, all within twenty (20) days after Borrower’s receipt of any notice from
Lender that amounts are or will be owing by Borrower to Lender pursuant to the
terms of this Section 2.06, then in such event, Borrower shall not be obligated
to pay to Lender any such amounts to the extent, but only to the extent, such
amounts are attributable to any period prior to the date of Borrower’s receipt
of such notice from Lender.

(c)    A certificate of Lender setting forth the amount or amounts necessary to
compensate Lender or its holding company, as the case may be, as specified in
Sections 2.06(a) or 2.06(b) shall be delivered to Borrower, demonstrating in
reasonable detail the calculation of the amounts. Borrower shall pay amounts due
under this Section 2.06 within ten (10) days after receipt of the corresponding
certificate.

(d)    Failure or delay on the part of Lender to demand compensation pursuant to
this Section shall not constitute a waiver of Lender’s right to demand such
compensation; but Borrower shall not be required to compensate Lender pursuant
to this Section for any increased costs or reductions incurred more than 180
days before the date that Lender notifies Borrower of the Change in Law giving
rise to such increased costs or reductions and of Lender’s intention to claim
compensation therefor; provided further that, if the Change in Law giving rise
to such increased costs or reductions is retroactive and if Lender notifies
Borrower of such Change of Law within 180 days after the adoption, enactment or
similar act with respect to such Change of Law, then the 180-day period referred
to above shall be extended to include the period from the effective date of such
Change of Law to the date of such notice.
Section 6.    Addition of Taxes Provisions. A new Section 2.09 is hereby added
to the Credit Agreement to hereafter read as follows:

Section 2.09    Taxes.

(a)    Withholding Taxes; Gross-Up; Payments Free of Taxes. Any and all payments
by or on account of any obligation of Borrower under any Credit Document shall
be made without deduction or withholding for any Taxes, except as required by
applicable law. If any applicable law (as determined in the good faith
discretion of an applicable withholding agent) requires the deduction or
withholding of any Tax from any such payment by a withholding agent, then the
applicable withholding agent shall be entitled to make such deduction or
withholding and shall timely pay the full amount deducted or withheld to the
relevant Governmental Authority in accordance with applicable law and, if such
Tax is an Indemnified Tax, then the sum payable by the Borrower shall be
increased as necessary so that after such deduction or withholding has been made
(including such deductions and withholdings applicable to additional sums
payable under this Section 2.09), Lender receives an amount equal to the sum it
would have received had no such deduction or withholding been made.

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(b)    Payment of Other Taxes by Borrower. Borrower shall timely pay to the
relevant Governmental Authority in accordance with applicable law, or at the
option of the Lender, timely reimburse it for, Other Taxes.

(c)    Evidence of Payment. As soon as practicable after any payment of Taxes by
Borrower to a Governmental Authority pursuant to this Section 2.09, Borrower
shall deliver to the Lender the original or a certified copy of a receipt issued
by such Governmental Authority evidencing such payment, a copy of the return
reporting such payment, or other evidence of such payment reasonably
satisfactory to Lender.

(d)    Indemnification by Borrower. Borrower shall indemnify Lender, within ten
(10) days after demand therefor, for the full amount of any Indemnified Taxes
(including Indemnified Taxes imposed or asserted on or attributable to amounts
payable under this Section) payable or paid by Lender or required to be withheld
or deducted from a payment to Lender and any reasonable expenses arising
therefrom or with respect thereto, whether or not such Indemnified Taxes were
correctly or legally imposed or asserted by the relevant Governmental Authority.
A certificate as to the amount of such payment or liability delivered to
Borrower by Lender shall be conclusive absent manifest error.

(e)    Treatment of Certain Refunds. If Lender determines, in its sole
discretion exercised in good faith, that it has received a refund of any Taxes
as to which it has been indemnified pursuant to this Section 2.09 (including by
the payment of additional amounts pursuant to this Section), it shall pay to the
indemnifying party an amount equal to such refund (but only to the extent of
indemnity payments made under this Section 2.09 with respect to the Taxes giving
rise to such refund), net of all out-of-pocket expenses (including Taxes) of
Lender and without interest (other than any interest paid by the relevant
Governmental Authority with respect to such refund). Such indemnifying party,
upon the request of Lender, shall repay to Lender the amount paid to Lender
(plus any penalties, interest or other charges imposed by the relevant
Governmental Authority) in the event Lender is required to repay such refund to
such Governmental Authority. Notwithstanding anything to the contrary in this
paragraph (e), in no event will Lender be required to pay any amount to any
indemnifying party pursuant to this paragraph (e), the payment of which would
place Lender in a less favorable net after-Tax position than Lender would have
been in if the Tax subject to indemnification and giving rise to such refund had
not been deducted, withheld or otherwise imposed and the indemnification
payments or additional amounts giving rise to such refund had never been paid.
This paragraph (e) shall not be construed to require Lender to make available
its Tax returns (or any other information relating to its Taxes that it deems
confidential) to the indemnifying party or any other Person.

(f)    Survival. Each party’s obligations under this Section 2.09 shall survive
the resignation or replacement of Lender or any assignment of rights by, or the
replacement of, Lender, the termination of the Commitment and the repayment,
satisfaction or discharge of all obligations under any Credit Document.

(g)    Defined Terms. For purposes of this Section 2.09, the term “applicable
law” includes FATCA.

Section 7.    Not FATCA “Grandfathered Obligation”. For purposes of determining
withholding Taxes imposed under FATCA, from and after the effective date of this
Amendment, Borrower and Lender shall treat the Credit Agreement as not
qualifying as a “grandfathered obligation” within the meaning of Treasury
Regulation Section 1.1471-2(b)(2)(i).

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Section 8.    Addition of Anti-Corruption Laws and Sanctions Provisions.

(a)    Section 5.09 of the Credit Agreement is hereby amended and restated in
its entirety to hereafter read as follows:

Section 5.09    Loan Proceeds. The proceeds of the Loans will be used to provide
funds for working capital, acquisition needs, capital expenditures and general
corporate purposes for Borrower. Borrower will not request any Loan or Letter of
Credit, and Borrower shall not use, and Borrower shall procure that its
Subsidiaries and its directors, officers, employees and agents shall not use,
the proceeds of any Loan (a) in furtherance of an offer, payment, promise to
pay, or authorization of the payment or giving of money, or anything else of
value, to any Person in violation of any Anti-Corruption Laws, (b) for the
purpose of funding, financing or facilitating any activities, business or
transaction of or with any Sanctioned Person, or in any Sanctioned Country, to
the extent such activities, businesses or transaction would be prohibited by
Sanctions if conducted by a corporation incorporated in the United States or the
European Union or (c) in any manner that would result in the violation of any
Sanctions applicable to any party hereto.

(b)    New Sections 4.20 and 5.12 are hereby added to the Credit Agreement to
hereafter read as follows:

Section 4.20    Anti-Corruption Laws and Sanctions. Each Obligor has implemented
and maintains in effect policies and procedures designed to ensure compliance by
such Obligor, its Subsidiaries and their respective directors, officers,
employees and agents with Anti-Corruption Laws and applicable Sanctions, and
such Obligor, its Subsidiaries and their respective officers and employees and,
to the knowledge of such Obligor, its directors and agents, are in compliance
with Anti-Corruption Laws and applicable Sanctions in all material respects.
None of (a) any Obligor, any Subsidiary or any of their respective directors,
officers or employees, or (b) to the knowledge of any such Obligor or
Subsidiary, any agent of any such Obligor or any such Subsidiary that will act
in any capacity in connection with or benefit from the credit facility
established hereby, is a Sanctioned Person. No Borrowing, Letter of Credit, use
of proceeds, or any other transaction contemplated by this Agreement or the
other Credit Documents will violate Anti-Corruption Laws or applicable
Sanctions.

Section 5.12 Compliance with Anti-Corruption Laws and Sanctions Laws. Each
Obligor and its Subsidiaries will maintain in effect and enforce policies and
procedures designed to ensure compliance by such Obligor, its Subsidiaries and
their respective directors, officers, employees and agents with Anti-Corruption
Laws and applicable Sanctions.

Section 9.    Designation of Equipment Inventory Collateral; Requisite
Commitment Coverage Ratio.

(a)    Replacement of Equipment Inventory Listing Exhibit. The listing of
Equipment Inventory attached as Exhibit E to the Credit Agreement is hereby
deleted in its entirety, and such Exhibit E is hereby replaced in its entirety
by the form of Exhibit E attached hereto and hereby made a part hereof for all
purposes.

(b)    Designated Equipment Inventory Collateral. In order to cause the Borrower
to hereafter be in compliance with the Commitment Coverage Ratio requirement of
Section 5.11(a) of

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the Credit Agreement, the Borrower hereby designates that all of the specific
Equipment Inventory of the Borrower described in Exhibit E attached hereto shall
be deemed to be the Equipment Inventory which serves as Collateral for the
Obligations. The Borrower hereby represents and warrants to the Lender that the
specific Equipment Inventory described in Exhibit E attached hereto is the
newest and most recently acquired rental compressor Inventory now owned and held
by the Borrower. The Borrower hereby agrees that contemporaneously herewith, the
Borrower shall execute and deliver to the Lender in Proper Form the requisite
amendments of the applicable Security Documents to evidence the designation of
all Equipment Inventory described in Exhibit E attached hereto as Collateral for
the Obligations.

Section 10.Modification of Notices Provisions. Section 8.08 of the Credit
Agreement is hereby amended and restated in its entirety to hereafter read as
follows:

Section 8.08     Notices. (a)    Except in the case of notices and other
communications expressly permitted to be given by telephone (and subject to
paragraph (b) below), all notices and other communications provided for herein
shall be in writing and shall be delivered to the respective parties at the
addresses shown herein by hand or overnight courier service, mailed by certified
or registered mail or sent by facsimile or electronic transmission. All such
notices and other communications (i) sent by hand or overnight courier service,
or mailed by certified or registered mail, shall be deemed to have been given
when received, (ii) sent by fax shall be deemed to have been given when sent,
provided that if not given during normal business hours for the recipient, such
notice or communication shall be deemed to have been given at the opening of
business on the next Business Day of the recipient, or (iii) delivered through
electronic communication to the extent provided in paragraph (b) below shall be
effective as provided in such paragraph.

(b)    Notices and other communications to Lender hereunder may be delivered or
furnished by electronic communications (including e-mail and internet or
intranet websites) pursuant to procedures approved by Lender; provided that the
foregoing shall not apply to notices pursuant to Article II unless otherwise
agreed by Lender. Each of Lender or Borrower may, in its discretion, agree to
accept notices and other communications to it hereunder by electronic
communications pursuant to procedures approved by it; provided that approval of
such procedures may be limited to particular notices or communications. All such
notices and other communications (i) sent to an e-mail address shall be deemed
received upon the sender’s receipt of an acknowledgement from the intended
recipient (such as by the “return receipt requested” function, as available,
return e-mail or other written acknowledgement), provided that if not given
during the normal business hours of the recipient, such notice or communication
shall be deemed to have been given at the opening of business on the next
Business Day for the recipient, and (ii) posted to an Internet or intranet
website shall be deemed received upon the deemed receipt by the intended
recipient, at its e-mail address as described in the foregoing clause (i), of
notification that such notice or communication is available and identifying the
website address therefor; provided that, for both clauses (i) and (ii) above, if
such notice, e-mail or other communication is not sent during the normal
business hours of the recipient, such notice or communication shall be deemed to
have been sent at the opening of business on the next Business Day of the
recipient.

(c)     Any party hereto may change its address, facsimile number or e-mail
address for notices and other communications hereunder by notice to the other
parties hereto.

Section 11.Representations True; No Default. The Borrower represents and
warrants that the representations and warranties contained in the Credit
Agreement and in the other Credit Documents are true and correct in all material
respects on and as of the date hereof as though made

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on and as of such date. The Borrower hereby certifies that except as expressly
described and set forth above in this Amendment, no event has occurred and is
continuing which constitutes a Default or an Event of Default under the Credit
Agreement or any of the other Credit Documents. Additionally, the Borrower
hereby represents and warrants to the Lender that that the resolutions of the
Board of Directors of the Borrower which are attached as an Exhibit A to the
Secretary's Certificate of even effective date with the Credit Agreement and
executed and delivered to Lender by the Secretary of Borrower in connection with
the Credit Agreement (i) remain in full force and effect as of the effective
date hereof, (ii) have not been modified, amended, superseded or revoked, and
(iii) authorize the execution of this Amendment and all other Credit Documents
to be executed contemporaneously herewith by the Borrower without the
requirement of any further consents, resolutions or authorizations of the Board
of Directors of the Borrower.

Section 12. Conditions Precedent to Effectiveness of this Amendment.
Notwithstanding any provisions to the contrary set forth in this Amendment, the
effectiveness of this Amendment, including without limitation, the increase of
the Revolving Loan Commitment, is expressly conditioned upon the satisfaction of
each of the following:

(a)    the renewal Note of even date herewith, executed by Borrower, payable to
the order of Lender in the original principal amount of $30,000,000.00, shall
have been furnished to Lender in Proper Form, and all Credit Documents
previously executed and delivered to Lender shall remain valid, enforceable and
in full force and effect;

(b)    no Default or Event of Default shall have occurred and be continuing as
of the effective date of this Amendment;

(c)    all of the representations and warranties contained in the Credit
Agreement and in all other Credit Documents shall be true and correct in all
material respects on and as of the date of this Amendment as though made on and
as of such date;

(d)    since the date of the most recently delivered financial statements
pursuant to the Credit Agreement, no Material Adverse Effect shall have
occurred, in the reasonable opinion of Lender;

(e)    all fees and expenses owed to Lender under any of the Credit Documents as
of the effective date of this Amendment shall have been paid in full;

(f)    all other due diligence items required by Lender shall have been received
and reviewed by Lender and otherwise be satisfactory in all respects to Lender;
and

(g)    all other conditions precedent deemed appropriate by Lender shall have
been satisfied.
  
Section 13. Ratification. Except as expressly amended hereby, the Credit
Agreement and the other Credit Documents shall remain in full force and effect.
The Credit Agreement, as amended, and all rights and powers created thereby or
thereunder and under the other Credit Documents are in all respects ratified and
confirmed and remain in full force and effect. The Borrower (a) hereby confirm
that the Security Documents previously executed and delivered by the Borrower
apply and shall continue to apply to all indebtedness (including without
limitation, the indebtedness now or hereafter evidenced by the Note of even date
herewith) evidenced by or arising pursuant to the Credit Agreement, as amended
hereby or any other Credit Documents, and (b) acknowledge that without this
ratification and confirmation, the Lender would not agree to the extension of
the Maturity Date and the modifications of the Credit Agreement which are
evidenced by this Amendment.

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Section 14. Definitions and References. Except as expressly modified by this
Amendment, capitalized terms which are not otherwise defined herein shall have
the meanings ascribed to them in the Credit Agreement. The term "Agreement" as
used in the Credit Agreement and the term "Credit Agreement" as used in the
other Credit Documents or any other instrument, document or writing furnished to
the Lender by the Borrower shall mean the Credit Agreement as hereby amended.

Section 15. Expenses; Additional Information. The Borrower shall pay to the
Lender all expenses incurred in connection with the preparation, negotiation and
execution of this Amendment. The Borrower shall furnish to the Lender all such
other documents, consents and information relating to the Borrower as the Lender
may reasonably require.

Section 16. Miscellaneous. This Amendment (a) shall be binding upon and inure to
the benefit of the Borrower and the Lender and their respective successors,
assigns, receivers and trustees (provided, however, that the Borrower shall not
assign its rights hereunder without the prior written consent of the Lender);
(b) may be modified or amended only by a writing signed by each party; (c) shall
be governed by and construed in accordance with the laws of the State of Texas
and the United States of America; (d) may be executed in several counterparts,
and by the parties hereto on separate counterparts, and each counterpart, when
so executed and delivered, shall constitute but one and the same agreement; and
(e) together with the Credit Documents, embodies the entire agreement and
understanding between the parties with respect to the subject matter hereof and
supersedes all prior agreements, consents and understandings relating to such
subject matter. The headings herein shall be accorded no significance in
interpreting this Amendment.

IN WITNESS WHEREOF, the Borrower and the Lender have caused this Amendment to be
signed by their respective duly authorized officers, effective as of the date
set forth above.

THE CREDIT AGREEMENT, AS AMENDED HEREBY, TOGETHER ALL OTHER CREDIT DOCUMENTS
CONSTITUTE A WRITTEN LOAN AGREEMENT AND REPRESENT THE FINAL AGREEMENT BETWEEN
THE PARTIES TO IT AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR,
CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO
UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

NATURAL GAS SERVICES GROUP, INC.,
a Colorado corporation

By:_______________________________________
Stephen C. Taylor, Chief Executive Officer
"Borrower"

JPMORGAN CHASE BANK, N.A.

By:     
Name:     
Title:     
"Lender"

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EXHIBIT E

DESIGNATED EQUIPMENT INVENTORY

(See attached spreadsheet with replacement Equipment Inventory listing)