Embodiments of this application disclose a tunnel keepalive method, a network device, a system, and a storage medium, and pertain to the field of communications technologies. In the embodiments of this application, before a failure occurs in communication between a UP device and a CP device, the UP device receives tunnel information synchronized by the CP device. After a failure occurs in communication between the UP device and the CP device, the UP device performs tunnel keepalive based on the tunnel information, that is, the UP device maintains a tunnel between the UP device and a remote network device. In this way, tunnel teardown is not triggered because of the failure in communication between the CP device and the UP device.