The underway and shift smoothly of automated mechanical transmission (AMT) vehicle are influenced by the clutch control property, it is difficult to be precisely handled by traditional PID control technology. The main reasons are the big hysteresis and nonlinear characteristics of clutch and actuation system. The gray prediction PID control technology in clutch control of AMT was analyzed. The control precision of clutch was improved by the proposed technology compared with traditional PID control technology. The gray prediction PID control could whiten certainly gray factors in the control system, improve the control quality and rubust of PID, and solve the problems of overrun and oscillation of clutch control. Thus, the underway and shift smoothly for vehicle were improved.