Intelligent vehicle formation can improve the driving status of vehicle platoon, increase road traffic flow, reduce traffic accidents, reduce environmental pollution and save energy. As an important part of cooperative platoon control system, cooperative platoon longitudinal speed following control has an important influence on the overall performance of vehicle platoon. To solve the longitudinal speed following control problem of cooperative vehicle platoon, a longitudinal following control strategy based on nonlinear proportion, integration, differentiation (PID) is proposed on the premise of fully considering the delay of vehicle actuator, the delay of vehicle communication and vehicle platoon stability. According to the communication topology structure of Predecessor-Leader Following, the information of platoon state is obtained, and the strategy of constant spacing is adopted. A layered vehicle platoon longitudinal controller is designed based on nonlinear PID control. The expected speed and expected acceleration are obtained by calculation, and the throttle opening or brake pressure is obtained according to the vehicle inverse dynamics model and PID feedback control to realize the longitudinal following control of the vehicle platoon. To verify the validity of the controller, co-simulation with MATLAB/Simulink and CarSim. The simulation results show that compared with the traditional PID control, the speed extremum, acceleration extremum and vehicle spacing extremum of the nonlinear PID controller designed in this paper can be improved by 0.14 m/s and 0.28 m/s, 0.05 m/s2 and 0.09 m/s2, 0.26 m and 0.22 m under two different conditions, which can effectively improve the longitudinal following state of the platoon, realize the speed cruise and formation maintenance of the vehicle platoon.