Abstract: Shift quality takes an important role in the automatic manual transmission systems. In order to improve the power performance and acceleration stability, reduce the shift shock and the undesired oscillations of driving output torque of AMT vehicle, this study puts forward a new control strategy based on multivariable Linear Quadratic (LQ) optimal control in estimating the feedback engine torque control. The main idea of this strategy is to obtain a linear quadratic state feedback tracking by solving the optimal control problem. The performance obtained with the proposed controller are compared with those achievable by means of a classical closed loop control strategy. Moreover, different operating conditions are used to test the controller performance. Numerical simulations show the good performance obtained by the proposed controller, which guarantees a decrease of the shift shock in the shift duration, an improve in the acceleration performance while enhance the shift quality.