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                                                                    Exhibit 12.1

                  CEO CERTIFICATION PURSUANT TO SECTION 302 OF
                         THE SARBANES-OXLEY ACT OF 2002

I, Yingjie Gao, certify that:

1. I have reviewed this annual report on Form 20-F of China GrenTech Corporation
Limited (the "Company");

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

3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects the
financial condition, results of operations and cash flows of the Company as of,
and for, the periods presented in this report;

4. The Company's other certifying officer and I are responsible for establishing
and maintaining disclosure controls and procedures (as defined in Exchange Act
Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as
defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the Company and have:

     a.   Designed such disclosure controls and procedures, or caused such
          disclosure controls and procedures to be designed under our
          supervision, to ensure that material information relating to the
          Company, including its consolidated subsidiaries, is made known to us
          by others within those entities, particularly during the period in
          which this report is being prepared;

     b.   Designed such internal control over financial reporting, or caused
          such internal control over financial reporting to be designed under
          our supervision, to provide reasonable assurance regarding the
          reliability of financial reporting and the preparation of financial
          statements for external purposes in accordance with generally accepted
          accounting principles;

     c.   Evaluated the effectiveness of the Company's disclosure controls and
          procedures and presented in this report our conclusions about the
          effectiveness of the disclosure procedures, as of the end of the
          period covered by this report based on such evaluation; and

     d.   Disclosed in this report any change in the Company's internal control
          over financial reporting that occurred during the period covered by
          the annual report that has materially affected, or is reasonably
          likely to materially affect, the Company's internal control over
          financial reporting; and

5. The Company's other certifying officer and I have disclosed, based on our
most recent evaluation of internal control over financial reporting, to the
Company's auditors and the audit committee of Company's board of directors (or
persons performing the equivalent functions):

     a.   All significant deficiencies and material weaknesses in the design or
          operation of internal control over financial reporting which are
          reasonably likely to adversely affect the Company's ability to record,
          process, summarize and report financial information; and

     b.   Any fraud, whether or not material, that involves management or other
          employees who have a significant role in the Company's internal
          control over financial reporting.

Date: July 15, 2008


By: /s/ Yingjie Gao
    ---------------------------------
Name: Yingjie Gao
Title: Chief Executive Officer