Exhibit 12.1**CERTIFICATION UNDER SECTION 302 OF THE SARBANES-OXLEY ACT**     I, Chia Song Hwee, certify that: 1. I have reviewed this annual report on Form 20-F of Chartered Semiconductor Manufacturing Ltd.;  2. Based on my knowledge, this annual report does not contain any untrue statement of a materialfact or omit to state a material fact necessary to make the statements made, in light of thecircumstances under which such statements were made, not misleading with respect to the period covered by thisreport;  3. Based on my knowledge, the financial statements, and other financial information included inthis report, fairly present in all material respects the financial condition, results of operations andcash flows of the company as of, and for, the periods presented in this report;  4. The company’s other certifying officer(s) and I are responsible for establishing andmaintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and15d-15(f)) for the company and have: a) Designed such disclosure controls and procedures, or caused such disclosurecontrols and procedures to be designed under our supervision, to ensure that material informationrelating to the company, including its consolidated subsidiaries, is made known to us by otherswithin those entities, particularly during the period in which this report is beingprepared;  b) Designed such internal control over financial reporting, or caused suchinternal control over financial reporting to be designed under our supervision, to provide reasonableassistance regarding the reliability of financial reporting and the preparation offinancial statements for external purposes in accordance with generally accepted accounting principles;  c) Evaluated the effectiveness of the company’s disclosure controls andprocedures and presented in this report our conclusions about the effectiveness of the disclosurecontrols and procedures, as of the end of the period covered by this report based on suchevaluation;  d) Disclosed in this report any change in the company’s internal control overfinancial reporting that occurred during the period covered by the annual report that has materiallyaffected, or is reasonably likely to materially affect, the company’s internal control overfinancial reporting; and 5. The company’s other certifying officer(s) and I have disclosed, based on our most recentevaluation of the internal control over financial reporting, to the company’s auditors and the auditcommittee of the company’s board of directors (or persons performing the equivalent functions): a) All significant deficiencies and material weaknesses in the design oroperation of internal control over financial reporting which are reasonably likely to adversely affect thecompany’s ability to record, process, summarize and report financial information; and  b) Any fraud, whether or not material, that involves management or otheremployees who have a significant role in the company’s internal control over financial reporting.        Date: March 15, 2007 /s/Chia Song Hwee   Chia Song Hwee  President and Chief Executive Officer