NEWBURY PARK, Calif.–(BUSINESS WIRE)—July 5, 2006–Electronic Sensor Technology (EST), a leading provider of innovative homeland security and environmental solutions, announced today the receipt of multiple orders from China Petroleum and Chemicals through its distributor, Beijing R&D Ltd. This is the result of a successful demonstration of the zNose® for monitoring and analysis of contaminated water in December, 2005, due to a chemical plant explosion near Songhua River in northeasternChina.  Substantial sales orders in China are expected in the coming months from the environmental monitoring and security market.

“We are pleased that the China Petroleum and Chemicals has chosen EST’s ultra-fast GC to monitor the water pollution,” said Dr. Teong C. Lim, President of EST.  “zNose® of EST has proven to be cost effective and meeting the expectations of the customer’s applications.”

The above order is part of a statement made in February of 2006 by Mr. Zhou Shengxian, director of the Chinese State EPA, indicating that control of water pollution will be the top priority for the government. He was quoted as saying, “The most urgent task for us is to check water pollution to ensure the safety of drinking water, and we must win the battle.”  Further detail on the subject is available through the following link:

http://news.xinhuanet.com/english/2006-02/14/content_4180459.htm

About Electronic Sensor Technology:

Founded in 1995, Electronic Sensor Technology has developed and patented a chemical vapor analysis process. We believe that the Company’s product line is positioned to eliminate key vulnerabilities in the homeland security market, specifically in maritime port, airport and border security applications.

SEC Filings and Forward-Looking Statements

This press release includes forward-looking statements, including the Company’s expectations regarding its ability to develop and access capital markets and its ability to achieve expected results in the chemical detection and analysis industry. The forward-looking statements are identified through use of the words “potential,” “anticipate,” “expect,” “planned” and other words of similar meaning. These forward-looking statements may be affected by the risks and uncertainties inherent in the chemical detection and analysis industry and in the Company’s business. The Company cautions readers that certain important factors may have affected and could in the future affect the Company’s beliefs and expectations, and could cause the actual results to differ materially from those expressed in any forward-looking statement made by or on behalf of the Company. For a discussion of these factors, please refer to our recent filings with the Securities and Exchange Commission, including our most recent report on Form 10-KSB. The Company undertakes no obligation to update forward-looking statements to reflect events or circumstances after the date hereof.

Contact:

Electronic Sensor Technology

Frank Zuhde, 805-480-1994 X 135

or

Aurelius Consulting Group, Inc.

Jon Cunningham, 407-644-4256 X 107