Network address translation method and device

The invention provides a network address translation method and device. The method includes the following steps of: generating a translation item of a message to be translated on a master network address translation device; making a backup of the translation item in the master network address translation device and a slave network address translation device of a network address translation device; and allowing the master network address translation device or the slave network address translation device to store and look up the translation item and perform network address translation on the corresponding message according to the translation item while taking over other network address translation devices to perform network address translation on the message corresponding to the translation item. The translation item includes a source network address of the message to be translated and a target network address obtained through network address translation of the source network address. The network address transl