**Exhibit 31.1**

**CERTIFICATIONPURSUANT TO 18 U.S.C. SECTION 1350,AS ADOPTED PURSUANT TOSECTION 302 OF THE SARBANES-OXLEY ACT OF 2002**

I, William M. Caldwell,IV, certify that:

(1) Ihave reviewed this Quarterly Report on Form 10-QSB of Advanced CellTechnology, Inc.;

(2) Basedon my knowledge, this report does not contain any untrue statement of amaterial fact or omit to state a material fact necessary to make the statementsmade, in light of the circumstances under which such statements were made, notmisleading with respect to the period covered by this report;

(3) Basedon my knowledge, the financial statements, and other financial informationincluded in this report, fairly present in all material respects the financialcondition, results of operations and cash flows of the small business issuer asof, and for, the periods presented in this report;

(4) Thesmall business issuer’s other certifying officer(s) and I are responsiblefor establishing and maintaining disclosure controls and procedures (as definedin Exchange Act Rules 13a-15(e) and 15d-15(e)) for thesmall business issuer and have:

(a) Designedsuch disclosure controls and procedures, or caused such disclosure controls andprocedures to be designed under our supervision, to ensure that material informationrelating to the small business issuer, including its consolidated subsidiaries,is made known to us by others within those entities, particularly during theperiod in which this report is being prepared;

(b) [Notapplicable];

(c) Evaluatedthe effectiveness of the small business issuer’s disclosure controls andprocedures and presented in this report our conclusions about the effectivenessof the disclosure controls and procedures, as of the end of the period coveredby this report based on such evaluation; and

(d) Disclosedin this report any change in the small business issuer’s internal control overfinancial reporting that occurred during the small business issuer’s mostrecent fiscal quarter (the small business issuer’s fourth fiscal quarter in thecase of an annual report) that has materially affected, or is reasonably likelyto materially affect, the small business issuer’s internal control overfinancial reporting; and

(5) Thesmall business issuer’s other certifying officer(s) and I have disclosed,based on our most recent evaluation of internal control over financialreporting, to the small business issuer’s auditors and the audit committee ofthe small business issuer’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 small business issuer’s ability to record, process,summarize and report financial information; and

(b) Anyfraud, whether or not material, that involves management or other employees whohave a significant role in the small business issuer’s internal control overfinancial reporting.
| Date:  May 15, 2006 |   |
|-------------------------------|--------|
|                          |   |
| /s/ WILLIAM M.  CALDWELL, IV  |   |
| William M. Caldwell,  IV      |   |
| Chief Executive  Officer      |   |

 

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