Due to the strong nonlinearity of the AC motor, it is difficult to obtain satisfied performance by the use of conventional PID control strategy. Self-adaptive control method is therefore needed to tackle with this problem. In this paper, a novel approach of fuzzy control is presented for the AC motor drives based on the PLC platform. The purpose is to enhance the speed control performance of AC motor by means of fuzzy logic. The hardware and software construction of the control system is described, and the fuzzy variables and fuzzy rules of the fuzzy controller are designed. Simulation test results show that the designed speed control system is efficient and reliable for the control of AC motor drives. Good performances such as faster dynamic response, smaller overshoot and higher accuracy compared with traditional PID controller are achieved.