ABSTRACT
<p><b>OBJECTIVE</b>The work presented here was to research into a kind of automatic control system that would be automatically linked to the working status of electronic endoscope.</p><p><b>METHODS</b>The image video output signal and signal of negative pressure sensor were used to be a sampling signal of automatic control circuit. An electronic switch of automatic control circuit was challenged the manual control device of the negative pressure system.</p><p><b>RESULTS</b>This system simplifies the operation procedures, enhances work efficiency, reduces energy consumption and improves the service life of the machine.</p><p><b>CONCLUSION</b>The paper concludes that this negative pressure automatic control system has many strengths like stable performance, easy installation and strong versatility. It also can be widely applied in different brand and different types of electronic endoscope in China.</p>