A NAT entry management method and a NAT device are disclosed. The method includes: receiving and storing, by a NAT device, a connection parameter, where the connection parameter includes an address of a controller; receiving a packet sent by a network device, where a source address of the packet is a private address of the network device and a destination address of the packet is the address of the controller; performing NAT on the packet, where an after-NAT source address of the packet is a public address; and when a static entry condition is met, generating a target static NAT entry, where the static entry condition includes that the destination address of the packet is the address of the controller. This can prevent aging of the NAT entry from affecting communication between the network device and the controller.