The gearshift of an automated mechanical transmission is performed by cutting off the power.The key to the gearshift of AMT is shift quality.Theinfluence of the control stategy during shifting processon shift quality is analysed.While resuming the power,the derivative of the speed differencebetween the clutch active disc and the clutch slave disc time instant is in direct proportion tothe discontinuity of the vehicle acceleration at the lock-up time instant.The large discontinuity of the vehicle acceleration will result in the jerk and the oscillation of vehicle that make passengers uncomfortable.A control stategy is proposed,that make small the derivative of the speed differencebetween the clutch active disc and the clutch slave disc by the integrated control of engine and clutch.The road test shows that the control stategy improves the shift quality.