A lateral and longitudinal coupling integrated control method based on model predictive control was proposed for the problem of vehicle trajectory tracking accuracy as well as stability under changing speed. In the three-degree-of-freedom vehicle dynamics model, the wheel driving force and steering wheel angle were used as control quantities to realize the integrated control of vehicle lateral-longitudinal motion in the form of a single controller. The optimal lateral-longitudinal control quantity was solved by designing the objective function and variable weight coefficients based on the coupling characteristics. Based on the fifth polynomial theory, a variable speed double-lane trajectory was designed to verify the tracking capability of the controller. The results show that the controller can effectively track the desired trajectory and variable vehicle speed with high accuracy and good real-time performance.