The invention discloses a self-adaptive maintaining method and device for an IP address of a maintained device. A maintaining gateway automatically obtains the IP address of the maintained device and a management device; the IP address of a first interface of the maintaining gateway is set as the IP address in a network segment the same to that of the IP address of the maintained device; the IP address of a second interface of the maintaining gateway is set as the IP address in the network segment the same to that of the IP address of the management device; after a data packet sent by the management device is received, a destination IP address of the data packet is replaced by the IP address of the maintained device, a source IP address is replaced by the IP address of the first interface of the maintaining gateway, and then the data packet is sent to the maintained device; and after the data packet sent by the maintained device is received, the destination IP address of the data packet is replaced by the IP address of the management device, the source IP address is replaced by the IP address of the second interface of the maintain gateway, and then the data packet is sent to the management device. According to the self-adaptive maintaining method and device for the IP address of the maintained device, the maintained device can be logged in for maintenance and management rapidly and conveniently.