Abstract: The automatic monitoring system is a kind of automatic security device used for monitoring,sound-recording,video-recording and alarming in emergency and handling the situation in some important areas. The control center of the system is a slightly changed single board computer TP-801.This reduces its cost and size and it can function in a wide range of environment. It is very suitable for the use in our country. The system has more than twenty management functions and real-time processing functions.Four types (TV,video-recorder,sound recorder and sound-monitor),eight-routing monitoring terminal (that is eight equipments can be used for each type) can be provided.They can monitor as many as 192 goals independently and concurrently and provide security officers with observational and recorded data with promptness and accuracy. The software consists of four parts,system management,function management, real-time processing and scan switchever.These form a two-hierarchy structure:inter-nal and external.The internal hierarchy,the system routime,executes the management functions of display,keyboard,ports and stacks.The other functions,such as normal scan,abnormal scan and giving alarm and its handling are completed by the external hierarchy called man-machine interface.Normal scan refers to the monitoring in a cir-cular manner of the goals independently and repeatedly by all kinds of terminals.There will be five secennds for each goal and then to the next.It will continue to work this way if nothing interferes. Abnormal scan means man’s interference.The goals can be deleted or inserted. Either a specific goal or any other goal can be used as the first scan point,changing the monitoring time is also feasible. Alarm function,when abnormal situation appears at a goal,a sound will be given by the singing device.At the same time the time and the number of alarming are reco-rded and the four-type terminals of certain routing are switched to this goal.The alar-ming state will stop only if someone gives some interference.