In active lane-changing scenarios for intelligent vehicles on multi-lane urban roads,relying solely on a single control algorithm for path tracking can lead to issues such as reduced accuracy or compromised stability.Here,we propose a decoupled control strategy that separates lateral and longitudinal trackings.First,the trajectory tracking task is decoupled into lateral position tracking and longitudinal velocity control.Subsequently,a feedforward-feedback lateral controller is designed based on the discrete Linear Quadratic Regulator (LQR) principle,and a longitudinal controller for position and speed is developed using a dual Proportional-Integral-Derivative (PID) principle.This integrated approach enables accurate tracking control of the planned trajectory.Finally,a co-simulation platform integrating Matlab/Simulink,PreScan,and CarSim is established for validation.Results show that the proposed decoupled control algorithm effectively tracks the reference trajectory under various lane-changing conditions,with all tracking errors within specified constraints.Moreover,compared to the Model Predictive Control (MPC),it results in a smaller centroid sideslip angle and yaw rate,offering superior driving stability and comfort.