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THE COMMON STOCK OF HOUSTON AMERICAN ENERGY CORP. ("HUSA") CONSTITUTES
SECURITIES THAT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED, OR THE APPLICABLE SECURITIES LAWS OF ANY STATE. THE COMMON STOCK MAY
NOT, AT ANY TIME, BE OFFERED FOR SALE, SOLD OR OTHERWISE TRANSFERRED WITHOUT
REGISTRATION UNDER THE ACT AND STATE LAWS, OR DELIVERY TO HUSA OF AN OPINION OF
LEGAL COUNSEL SATISFACTORY TO HUSA THAT SUCH REGISTRATION IS NOT REQUIRED.
RESTRICTIONS ON TRANSFER WILL BE IMPRINTED ON THE DOCUMENTS EVIDENCING THE
COMMON STOCK TO THE FOREGOING EFFECTS.

THE PURCHASE OF COMMON STOCK INVOLVES A HIGH DEGREE OF RISK AND SHOULD BE
CONSIDERED ONLY BY PERSONS WHO CAN BEAR THE RISK OF LOSING THEIR ENTIRE
INVESTMENT.

HOUSTON AMERICAN ENERGY CORP.

Common Stock, par value $.001 per share

SUBSCRIPTION AGREEMENT

Houston American Energy Corp.
c/o Sanders Morris Harris Inc.
600 Travis, Suite 3100
Houston, Texas 77002

Ladies and Gentlemen:

This will confirm my agreement to become a stockholder of Houston American
Energy Corp. ("HUSA" or the “Company”) and to purchase shares of common stock,
par value $.001 per share, in HUSA (the "Common Stock"). I/we hereby acknowledge
receipt of the Preliminary Confidential Private Placement Memorandum dated
April 11, 2006 and the Final Confidential Private Placement Memorandum dated
April 24, 2006, each with the exhibits thereto (collectively, the "Memorandum"),
with respect to HUSA. The Memorandum describes the terms under which the Common
Stock is being offered to subscribers.

1.     Subscription and Sale.

1.1    Subscription. Subject to the terms and conditions of this Agreement and
the provisions of the Memorandum, I/we irrevocably subscribe for, and agree to
purchase the number of shares of Common Stock of HUSA for the subscription price
indicated on the Signature Page. I am/we are tendering to HUSA (a) a completed,
signed, and dated copy of this Agreement, (b) a completed, signed, and dated
Purchaser's Questionnaire, and (c) a certified check or bank check in the amount
of the subscription price (or I am/we are concurrently wire transferring such
amount to the Escrow Agent or authorizing the payment of such amount from my
account at Sanders Morris Harris Inc.).

1.2    Acceptance or Rejection of Subscription. All funds tendered by me/us will
be held in a segregated subscription account pending acceptance or rejection of
this Agreement and the closing of my/our purchase of the Common Stock. This
Agreement will either be accepted, in whole or in part, subject to the prior
sale of the Common Stock, or rejected, by HUSA as promptly as practicable. If
this Agreement is accepted only in part, I/we agree to purchase such smaller
number of shares of Common Stock as HUSA determines to sell to me/us. If this
Agreement is rejected for any reason or no reason, including, the termination of
the offering of the Common Stock by HUSA, this Agreement and all funds tendered
with it will be promptly returned to me/us, without deduction of any kind, and
this Agreement will be void and of no further force or effect. Deposit and
collection of the check tendered, or receipt of funds wired or delivered from
my/our account at Sanders Morris Harris Inc., with this Agreement will not
constitute acceptance of this Agreement.

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1.3    Closing. Subscriptions will be accepted at one or more closings, as
described in the Memorandum. On closing, the subscription evidenced hereby, if
not previously rejected, will, in reliance on my/our representations and
warranties, be accepted, in whole or in part, and HUSA will execute a copy of
this Agreement and return it to me/us. If my/our subscription is accepted only
in part, this Agreement will be marked to indicate such fact, and HUSA will
return to me/us the portion of the funds tendered by me/us representing the
unaccepted portion of my/our subscription, without deduction of any kind. The
Common Stock subscribed for will not be deemed to be issued to, or owned by,
me/us until HUSA has accepted this Agreement.

2.      Representations, Warranties, and Covenants of the Purchaser. I/we
represent, warrant, and covenant to HUSA that:

2.1    General:

(a)    If I am a natural person, I have the legal capacity and all requisite
authority to enter into, execute, and deliver the Transaction Documents, to
purchase the Common Stock, and to perform all the obligations required to be
performed by me thereunder. If we are a corporation, partnership, limited
liability company, trust, estate, or other entity, we are authorized to purchase
the Common Stock and otherwise to comply with our obligations under the
Transaction Documents. The person signing this Agreement on behalf of such
entity is duly authorized by such entity to do so. The Transaction Documents are
my/our valid and binding agreements and enforceable against me/us in accordance
with their terms.

(b)    My/our principal residence is in the jurisdiction indicated herein, or if
we are a corporation, partnership, limited liability company, trust, estate, or
other entity, we are organized and qualified under the law of the state
indicated below and I/we have no intention of becoming a resident or domiciliary
of any jurisdiction other than the one indicated by our address.

(c)    I am/we are subscribing to purchase the Common Stock solely for my/our
own account, for investment, and not with a view to, or for resale in connection
with, any distribution. I am/we are not acquiring the Common Stock as an agent
or otherwise for any other person.

2.2    Information Concerning the Offering:

(a)    I/we have received, carefully read, and understood the Memorandum. I/we
have not been furnished any offering literature other than the Memorandum and
the Exhibits attached thereto and have relied only on the information contained
therein and my/our own due diligence efforts and inquiries with respect to the
Offering. The Common Stock was not offered to me/us by any means of general
solicitation or general advertising.

(b)    I/we understand that the offering of the Common Stock is being made
without registration of the Common Stock under the Securities Act of 1933, as
amended (the "Act"), or any state securities or blue sky laws in reliance on
exemptions from such registration, and that such reliance is based in part on my
representations and warranties set forth in this Section 2 and on the
information set forth in the Purchaser's Questionnaire tendered by me/us to HUSA
with this Agreement.

(c)    In formulating a decision to invest in the Common Stock, I/we (and my/our
Purchaser Representative (as defined in Rule 501(h) of Regulation D under the
Act), if any) have been given the opportunity to ask questions of, and to obtain
any information necessary to permit me to verify the accuracy of the information
set forth in the Memorandum from, representatives of HUSA and have been
furnished all such information so requested. I/we have not relied or acted on
the basis of any representations or other information purported to be given on
behalf of HUSA except as set forth in the Memorandum (it being understood that
no person has been authorized by HUSA to furnish any representations or other
information except as set forth in the Memorandum).

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(d)    I/we understand that the purchase of the shares of Common Stock involves
various risks and that an investment in HUSA should be regarded as speculative
and involving a high degree of risk. I am/we are fully aware of the nature of my
investment in HUSA and the lack of liquidity of an investment in the shares of
Common Stock being offered pursuant to the Offering, because the shares may not
be sold, transferred, or otherwise disposed of except pursuant to an effective
registration statement under the Act or an exemption from such registration, and
that in the absence of such registration or exemption, the shares of Common
Stock must be held indefinitely.

(e)    I/we understand that no federal or state agency has passed upon the
Common Stock of HUSA or made any finding or determination concerning the
fairness or advisability of an investment in HUSA.

2.3   Status of Subscriber, Additional Information:

(a)    If we are a corporation, partnership, limited liability company, trust,
estate, or other entity, we are an "accredited investor," as that term is
defined in Rule 501(a) of Regulation D under the Act (see the Purchaser's
Questionnaire for a list of the types of accredited investors) and meet the
experience standards set forth in Section 2.3(b) below. If I am a natural
person, I am at least 21 years of age and am an "accredited investor" and meet
the experience standards set forth in Section 2.3(b) below.  
 
(b)    I (together with my Purchaser Representative, if any), or if we are a
corporation, partnership, limited liability company, trust, estate, or other
entity, we by and through our officers, directors, trustees, managers, partners,
employees, or other advisors, (i) are experienced in evaluating companies such
as HUSA, (ii) have determined that the shares of Common Stock are a suitable
investment for me/us, and (iii) have such knowledge, skill, and experience in
business, financial, and investment matters so that I am/we are capable of
evaluating the merits and risks of an investment in the Common Stock. To the
extent necessary, I/we have retained, at my/our expense, and relied upon,
appropriate professional advice regarding the investment, tax, and legal merits
and consequences of this Agreement and owning the Common Stock, and I/we and
my/our advisers or representatives have investigated my/our investment in HUSA
to the extent I/we and they have deemed advisable. I/we have the financial
ability to bear the economic risks of our entire investment for an indefinite
period and no need for liquidity with respect to our investment in HUSA, and, if
I am a natural person, I have adequate means for providing for my current needs
and personal contingencies.

(c)    I/we agree to furnish any additional information requested to assure
compliance with the Act and state securities laws in connection with the
purchase and sale of the Common Stock. If there is any material change in the
information I/we are furnishing hereunder prior to the date this Agreement is
accepted, I/we will immediately furnish such revised or corrected information to
HUSA.

2.4   Restrictions on Transfer or Sale of the Common Stock:

(a)    I /we will not sell, assign, pledge, give, transfer, or otherwise dispose
of any the Common Stock or any interest therein, or make any offer or attempt to
do any of the foregoing, except pursuant to a registration of the Common Stock
under the Act and applicable state securities laws or in a transaction that is
exempt from the registration provisions of the Act and any applicable state
securities laws. I/we understand that HUSA will not be under any obligation to
register the Common Stock under the Act or any state securities law (except as
provided in the Registration Rights Agreement (as hereinafter defined)) or to
comply with the terms of any exemption provided under the Act or any state
securities law with respect to the Common Stock.

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(b)    I/we have not offered or sold any portion of my/our Common Stock and have
no present intention of dividing my/our Common Stock with others or of reselling
or otherwise disposing of any portion of my/our shares of Common Stock either
currently or after the passage of a fixed or determinable period of time or upon
the occurrence or nonoccurrence of any predetermined event or circumstance.

2.5    Independent Nature of Investor's Obligations and Rights. My/our
obligations under this Agreement, the Registration Rights Agreement, and any
other documents delivered in connection herewith and therewith (collectively,
the "Transaction Documents") are several and not joint with the obligations of
any other purchaser of Common Stock, and I/we shall not be responsible in any
way for the performance of the obligations of any other purchaser of Common
Stock under any Transaction Document. My/our decision to purchase Common Stock
pursuant to the Transaction Documents has been made by me/us independently of
any other purchaser of Common Stock. Nothing contained herein or in any
Transaction Document, and no action taken by any purchaser of Common Stock
pursuant thereto, shall be deemed to constitute such purchasers as a
partnership, an association, a joint venture, or any other kind of entity, or
create a presumption that the purchasers of Common Stock are in any way acting
in concert or as a group with respect to such obligations or the transactions
contemplated by the Transaction Document. I/we acknowledge that no other
purchaser of Common Stock has acted as agent for me/us in connection with making
my/our investment hereunder and that no other purchaser of Common Stock will be
acting as my/our agent in connection with monitoring my/our investment in the
Common Stock or enforcing my/our rights under the Transaction Documents. I/we
shall be entitled to independently protect and enforce my/our rights, including
without limitation the rights arising out of this Agreement or out of the other
Transaction Documents, and it shall not be necessary for any other purchaser of
Common Stock to be joined as an additional party in any proceeding for such
purpose.

2.6    Due Authority, Etc. If we are a corporation, partnership, limited
liability company, trust, estate, or other entity: (a) we are duly organized,
validly existing, and in good standing under the laws of the jurisdiction of our
formation and have all requisite power and authority to own our properties and
assets and to carry on our business, and at HUSA's request, will furnish it with
copies of our organizational documents, (b) we have the requisite power and
authority to execute the Transaction Documents and to carry out the transactions
contemplated hereby, (c) our execution and performance of the Transaction
Documents do not and will not result in any violation of, or conflict with, any
term of our charter, bylaws, partnership agreement, operating agreement or
regulations, or indenture of trust, as the case may be, or any instrument to
which we are a party or by which we are bound or any law or regulation
applicable to us, (d) our execution and performance of the Transaction Documents
has been duly authorized by all necessary corporate, partnership, or other
action, (e) we were not specifically formed to invest in HUSA, and (f) the
individual who has executed the Transaction Documents on our behalf was duly
authorized to do so by all requisite corporate, partnership, or other action
and, on request of HUSA, we will furnish appropriate evidence of the authority
of such individual to act on our behalf.

2.7    Valid Obligation. This Agreement has been duly executed and delivered
me/us or on our behalf and, if and when accepted by HUSA, in whole or in part,
will constitute my/our legal, valid, and binding obligation, enforceable in
accordance with its terms (except as limited by principles of equity or
bankruptcy, insolvency, or other similar laws affecting enforcement of
creditors' rights generally).

2.8    ERISA Matters. If we are an employee benefit plan within the meaning of
the Employee Retirement Income Security Act of 1974, as amended ("ERISA"):

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(a)    We and our plan fiduciaries are not affiliated with, and are independent
of HUSA, and are informed of and understand HUSA's investment objectives,
policies, and strategies.

(b)    We represent that the purchase of the Common Stock will not involve any
transaction that is subject to the prohibition of Section 406 of ERISA or in
connection with which a penalty could be imposed under Section 502(i) of ERISA
or a tax could be imposed pursuant to Section 4975 of the Internal Revenue Code
of 1986, as amended (the "Code").

(c)    The trustee or other plan fiduciary directing the investment:

(i)    in making the proposed investment, is aware of and has taken into
consideration the diversification requirements of Section 404(a)(1)(C) of ERISA;
and

(ii)    has concluded that the proposed investment in HUSA is prudent and is
consistent with the other applicable fiduciary responsibilities under ERISA.

(d)    This Agreement has been duly executed on our behalf by a duly designated
Named Fiduciary (within the meaning of Section 402(a)(2) of ERISA).

(e)    If we are an individual retirement account (IRA) or employee benefit plan
not subject to Title I of ERISA, such as a governmental or church plan, the
owner of the individual retirement account or other fiduciary directing the
investment of the plan has concluded that the proposed investment in Common
Stock of Common Stock is prudent and consistent with its fiduciary
responsibilities, if any.

2.9    Fees and Commissions. No fees or commissions have been paid or are
payable by me/us in connection with this Agreement and the issuance of shares of
Common Stock to me/us.

3.     Registration Rights Agreement; Power of Attorney. I/we further agree to
be bound by the terms of and hereby execute the Registration Rights Agreement
among HUSA and the purchasers of the shares of Common Stock of HUSA being
offered pursuant to the Offering (the "Registration Rights Agreement"). By
signing below, I/we irrevocably constitute and appoint Sanders Morris Harris
Inc., a Texas corporation ("SMH"), as my/our true and lawful agent and
attorney-in-fact with full power of substitution and full power and authority in
my/our name, place, and stead to execute and deliver the Registration Rights
Agreement and to take such actions as may be necessary or appropriate to carry
out the terms of the Registration Rights Agreement. The power of attorney hereby
granted will be deemed coupled with an interest, will be irrevocable, and will
survive and not be affected by my/our subsequent death, incapacity, dissolution,
insolvency, or termination or any delivery by me/us of an assignment in whole or
in part of my/our shares of Common Stock. The foregoing power of attorney may be
exercised by SMH either by signing separately or jointly as attorney-in-fact for
each or all of the subscribers for the Common Stock or by a single signature of
SMH acting as attorney-in-fact for all of them. HUSA may rely and act upon any
writing believed in good faith to be signed by SMH or any authorized
representative of SMH, and may assume that all actions of SMH and any authorized
representative of SMH have been duly authorized by me/us.

4.     Waiver, Amendment, Binding Effect. Neither this Agreement nor any
provisions hereof shall be modified, changed, discharged, or terminated except
by an instrument in writing, signed by the party against whom any waiver,
change, discharge, or termination is sought. The provisions of this Agreement
shall be binding upon and accrue to the benefit of the parties hereto and their
respective heirs, legal representatives, successors, and assigns.

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5.    Assignability. Neither this Agreement nor any right, remedy, obligation,
or liability arising hereunder or by reason hereof shall be assignable by HUSA
or me/us without the prior written consent of the other.

6.    Applicable Law. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF TEXAS, WITHOUT REGARD TO THE CONFLICT OF LAWS
PROVISIONS THEREOF.

7.    Counterparts. This Agreement may be executed in any number of counterparts
and by facsimile, each of which when so executed and delivered shall be deemed
to be an original and all of which together shall be deemed to be one and the
same agreement.

8.    Notices. All notices and other communications provided for herein shall be
in writing and shall be deemed to have been duly given if delivered personally
or sent by registered or certified mail, return receipt requested, postage
prepaid:

 
(a)
If to HUSA, to it at the following address:

   
Houston American Energy Corp.

   
801 Travis, Suite 2020

   
Houston, Texas 77002

   
Attn: John F. Terwilliger

 
(b)
If to me/us at the address

   
set forth on the signature page hereto;

or at such other address as either party shall have specified by notice in
writing to the other.

9.     Survival. All representations, warranties, and covenants contained in
this Agreement shall survive (i) the acceptance of the Subscription by HUSA,
(ii) changes in the transactions, documents and instruments described in the
Memorandum, and (iii) my death or disability.

10.    Notification of Changes. I/we hereby covenant and agree to notify HUSA
upon the occurrence of any event prior to the closing of the purchase of the
shares of Common Stock pursuant to this Agreement, which would cause any
representation, warranty, or covenant by me/us contained in this Agreement to be
false or incorrect.

11.    Purchase Payment. The purchase price is being paid herewith by delivery
of either a certified check or bank check payable to "HUSA - Escrow Account” or
alternatively, by wire transfer or authorization of Sanders Morris Harris Inc.
to pay from my account. All payments made as provided in this Paragraph 11 shall
be deposited as soon as practicable and held in a segregated escrow account
until the earlier to occur of (a) the sale of all of the securities in this
Offering or (b) the termination of this Offering.

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HOUSTON AMERICAN ENERGY CORP.
Subscription Agreement
Signature Page

IN WITNESS WHEREOF, the undersigned has executed this Subscription Agreement on
_____________, 2006.

NUMBER OF SHARES OF COMMON STOCK SUBSCRIBED FOR:
 
   
AMOUNT OF SUBSCRIPTION ($3.00 PER SHARE):
$
    

 

NAME OF SUBSCRIBER(S):
                   
(1)
    
Signature:
     
 
(Please print name)
 
 Date:
        
 Name:
 
     
 Title:
 
             
Joint Tenant/Tenant in Common (if applicable):
                   
(2)
    
Signature:
       
(Please print name)
 
 Date:
              
ADDRESS (including mailing address, if applicable):
                                                                            
TAXPAYER I.D. NUMBER OR SOCIAL SECURITY NUMBER OF EACH SUBSCRIBER:
                               

 
TYPE OF OWNERSHIP:

 
(   )
Individual

 
(   )
Tenants in common

 
(   )
Joint tenants with right of survivorship

 
(   )
Community property (check only if resident of community property state)

 
(   )
Partnership (1)

 
(   )
Corporation (2)

 
(   )
Trust (3)

 
(   )
Limited Liability Company (4)

 
(   )
Employee Benefit Plan under ERISA

 
(    )
Other (please specify:____________________)

________________
1.
Please enclose a copy of the partnership agreement and a current list of all
partners.

2.
Please enclose a copy of the articles or certificate of incorporation, bylaws,
and a resolution authorizing this investment and indicating the authority of the
signatory hereto.

3.
Please enclose a copy of the trust instrument.

4.
Please enclose a copy of the articles of formation and members' agreement or
regulations.

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HOUSTON AMERICAN ENERGY CORP.
Acceptance of Subscription
 
Agreed and accepted as to $ ___________________  Dated:___________________

 
HOUSTON AMERICAN ENERGY CORP.
                   
By:
        
Name:
      
Its:
      

 
 

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