It is aimed at the phenomenon that the parallel current sharing effect of the buck(Buck) converter in the chaotic state is not good, and the steady-state and dynamic characteristics of the current sharing are poor. Firstly, the segmented smooth switching model and discrete model of the voltage-controlled Buck converter are established, and the path to chaos is analyzed. Then the drive and response systems with different initial values are established. The designed terminal sliding mode control rate is applied to the response system to realize the chaotic synchronization control of the parallel system. Based on the chaotic synchronization characteristics, the parallel current sharing control of the voltage-controlled Buck converter can be realized. Finally, the parallel system model after applying control is built through the Matlab/Simulink simulation platform for experimental simulation. The results show that the current sharing error of the parallel system is close to 0, and when the input voltage changes abruptly, the current sharing error does not change, indicating that after applying terminal sliding mode control, the Buck converter parallel current sharing error is small and has a good steady state and dynamic characteristics.