Exhibit 10.1

THIRD AMENDMENT OF CREDIT AGREEMENT

THIS THIRD AMENDMENT OF CREDIT AGREEMENT (hereinafter referred to as the
"Amendment"), dated effective as of November 19, 2014, 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:

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 (said Credit Agreement, and that certain
Second Amendment of Credit Agreement dated December 30, 2013, executed by and
between the Borrower and the Lender (said Credit Agreement, shall hereinafter be
collectively referred to as the "Credit Agreement").

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, 2017, (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 November 19, 2014, 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. 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 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

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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 3. 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 4. 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, the increase of the Commitment and the modifications of the
Credit Agreement which are evidenced by this Amendment.

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Section 5. 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 6. 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 7. 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: /s/ Stephen C. Taylor
Stephen C. Taylor, Chief Executive Officer

"Borrower"

JPMORGAN CHASE BANK, N.A.

By: /s/ Gabe Terrazas     
Gabe Terrazas, Senior Banker

"Lender"