Double module terminal and its method for selecting resident network

A double module terminal and its resident network selecting method are disclosed in the present invention, wherein, the double module terminal resident network selecting method comprises the following steps: a terminal judges whether or not to be able to search the first mode cell and reside successfully, if does, then entering the first mode cell idle mode; otherwise, the terminal judges whether or not be able to search the second mode cell and reside successfully, if does, then entering the second mode cell idle mode, otherwise, the terminal supplies limited service only. The double module terminal and its resident network selecting method of the present invention lead the terminal more likely to reside 3G cell, and avoid redundant electric consumption, so as to improve the system performance.