An model predictive control(MPC) algorithm based cooperative adaptive cruise control(CACC) fleet driving trajectory tracking approach is proposed under the V2X environment to address the issue of safety and stability of CACC fleet driving trajectory in the curved area. First, the driving conditions and longitudinal balance of the CACC fleet in the bend region are analyzed, and a model of vehicle dynamics based on the Newton's second law is established. Second, the CACC fleet realizes real-time interaction of state information between vehicles using V2X technology, and introduces a fleet safety distance control model with variable spacing based on the MPC algorithm of vehicle kinematics, then a trajectory tracking model for curved areas is proposed. Finally, the model is solved using quadratic programming. Analysis of the experimental results shows that the CACC fleet in a V2X environment can ensure the safety, stability, and comfort of the drivers and passengers to varying degrees while driving in the bend. It effectively verifies the feasibility of the MPC algorithm-based trajectory tracking control strategy for the CACC fleet driving in curved areas under the V2X environment.