**Exhibit 31.1**

Certification ofPrincipal Executive OfficerPursuant to Rule 13a-14(a) of theSecurities Exchange Act of 1934

I, Michael J.Mauceli, certify that:

1.     I have reviewed this annualreport on Form 10-K of Reef Global Energy VI, L.P. for the fiscal year endedDecember 31, 2006;

2.     Based on my knowledge, thisannual report does not contain any untrue statement of a material fact or omitto state a material fact necessary to make the statements made, in light of thecircumstances under which such statements were made, not misleading withrespect to the period covered by this report;

3.     Based on my knowledge, thefinancial statements, and other financial information included in this report,fairly present in all material respects the financial condition, results ofoperations and cash flows of the registrant as of, and for, the periodspresented in this report;

4.     The registrant’s othercertifying officer and I are responsible for establishing and maintainingdisclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e)and 15d-15(e)) for the registrant and have:

a)     Designedsuch disclosure controls and procedures, or caused such disclosure controls andprocedures to be designed under our supervision, to ensure that materialinformation relating to the registrant, including its consolidatedsubsidiaries, is made known to us by others within those entities, particularlyduring the period in which this report is being prepared;

b)    Evaluatedthe effectiveness of the registrant’s disclosure controls and procedures andpresented in this report our conclusions about the effectiveness of thedisclosure controls and procedures, as of the end of the period covered by thisreport based on such evaluation; and

c)     Disclosedin this report any change in the registrant's internal control over financialreporting that occurred during the registrant's fourth fiscal quarter that hasmaterially affected, or is reasonably likely to materially affect, theregistrant's internal control over financial reporting.

5.     The registrant’s othercertifying officer and I have disclosed, based on our most recent evaluation ofinternal control over financial reporting, to the registrant’s auditors and theaudit committee of registrant’s board of directors (or persons performing theequivalent functions):

a)     Allsignificant deficiencies and material weaknesses in the design or operation ofinternal control over financial reporting which are reasonably likely toadversely affect the registrant’s ability to record, process, summarize andreport financial information; and

b)    Anyfraud, whether or not material, that involves management or other employees whohave a significant role in the registrant’s internal control over financialreporting.
| Date: April 16, 2007 | By: Reef Oil & Gas Partners, L.P.     |
|----------------------|-------------------------------------------|
|                 | Managing General  Partner                 |
|                 |                                      |
|                 |                                      |
|                 | By: Reef Oil  & Gas Partners, GP, LLC |
|                 | By:                                       | /s/ Michael J.  Mauceli |
|                 | Michael J.  Mauceli                       |
|                 | Manager and  Member                       |
|                 | (principal  executive officer)            |

 

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