In order to improve the shift quality of a two-speed inverse automated manual transmission (I-AMT) of electric vehicle (EV), optimal control is used to generate the reference trajectories of the clutch slip speed and motor torque. The offline optimization results are fitted and used for online implementation. In order to compensate the disturbances and modeling errors, a proportional integral derivative (PID) controller is added to ensure the closed-loop control performance. The proposed controller is almost free of calibration effort, because the feedforward part of the proposed controller considered the simple but dominant system dynamics. Finally, the control algorithm is confirmed through large amounts of tests on a complete powertrain simulation model, and the designed controller can provide satisfactory performance even under large variation of vehicle mass and road grade.