Abstract: A modular design method to recognize the operahng mode in process of complex production is provided. The enhre recognihon task is divided into two sub-modules; modeling module, trained off-line, and decision module, Performed on-line.In modeling module, the adaphve time-delay neura network is used to construct various predicting models which correspond to different operating modes. In decision module, for a new sequence, which operating mode it belong to is deduced depending on matching degree between this new sequence and all predichng models. The simulation results show the effectiveness of the method.