A control plane (CP) device switching method includes that when a user plane (UP) device in a forwarding-control separation system detects that performance of communication between the UP device and an active CP device does not meet a normal communication condition, and performance of communication between the UP device and a standby CP device meets the normal communication condition, the UP device sends a switching request to the standby CP device. When detecting that a quantity of UP devices that each send the switching request is greater than or equal to a first quantity threshold, the standby CP device may indicate each UP device in the forwarding-control separation system to switch to the standby CP device.