A software upgrade method and a device, which relate to the field of communications technologies. Software upgrade is performed for a terminal by using an access device located in a local area network, which avoids access to the Internet when software of the terminal is upgraded and reduces load or burden of a network. The method includes: receiving, by an access device, software information sent by at least one terminal device in a local area network in which the access device is located, and performing a comparison between the software information sent by the at least one terminal device and software information stored in the access device, to determine whether to-be-updated target software exists; if it is determined that to-be-updated target software exists in the at least one terminal device, transmitting update information of the target software to a terminal device corresponding to the target software.