The present invention relates to a method, a terminal and a server for allocating a signal route resource in a Video On Demand (VOD) service. The method includes: sending a route detection message to a VOD server; receiving a route resource list replied by the VOD server; receiving a route detection stream according to a signal route resource in the obtained route resource list; judging, according to the received route detection stream, whether the signal route resource corresponding to the received route detection stream is valid; and reporting valid signal route resource information to the VOD server. Through a signal route detection method, a location of a VOD terminal device is automatically identified, so that roaming of the VOD terminal device may be realized, and when a coverage relation of the terminal is changed, the VOD service may be normally supported without any additional processing.