The traditional trajectory tracking control method is limited in application scenarios and has low accuracy. In order to realize the vehicle transverse and longitudinal joint control and improve the trajectory tracking effect of unmanned vehicles in structured scenarios this paper established the vehicle tracking error model under the natural coordinate system and designed the vehicle transverse and longitudinal coupling controller based on the combination of LQR and PID. At the transverse control level in order to eliminate the stability error of the system the introduction of the feedforward control quantity realized the overall stability of the system reducing the transverse error generated during the actual operation of the vehicle and improving the stability of the control process. At the longitudinal control level a PID control strategy was used to achieve an accurate match between the actual speed and the planned speed and between the actual position and the planned position of the vehicle. A joint simulation platform was built by MATLAB / Simulink and Carsim to verify various conditions such as daily parking driving into the main road and overtaking. The simulation results showed that the transverse-longitudinal joint controller designed in this paper could control the trajectory tracking error of the vehicle within an acceptable range and the trajectory tracking effect could meet passengers?? requirements for vehicle comfort. Therefore the controller designed in this paper has certain stability and accuracy.