Abstract: Immunity,a basic physiology,is derived from the research of anti-infection,whose organism recognizes antigenicity eyewinkers and rejects them. Modern bionic technologies use immunity to solve nonlinear programming problems and form particular artificial immune system(AIS)which represents feasible solutions through antibodies and embodies constrains and objective function through antigen. AIS also adopts anticipant productive rate to define selection probabilities which can be used for random search of the whole optimal solution. According to the application of AIS to the short-term optimal scheduling of hydro plants in cascade,the AIS is confirmed.