Abstract: The AI (Artificial Intelligent) control described in this paper can realize an adaptive control without demand for establishing any mathe-matical model of the plant to be controlled, for it provides itself with a series of expert's functions:on-line auto-adjustment and on-line self- optimization of the operation parameters of the controller, self-selection among the control strategies, etc..Applications of AI control in medium as well as in low temperature system are also described,and moreover, all of these are carried out by means of one of the simplest computers.