Exhibit 31.1

      Certification pursuant to Rule 13a-14(a)/15d-14(a) of the Securities
                              Exchange Act of 1934

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I, Barry S. Howe, certify that:

1.   I have reviewed this annual report for the fiscal year ended December 31,
2007 of ELECTRONIC SENSOR TECHNOLOGY, INC. (the "Company");

2.   Based on my knowledge, this 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 financing 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 principals;

(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 controls and 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 Company's most recent fiscal
quarter (the Company's fourth fiscal quarter) 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:  April 8, 2008                       /s/ Barry S. Howe
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                                           Barry S. Howe
                                           President and Chief Executive Officer
                                           (Principal Executive Officer)