A method for switching communication network used in a first electronic device which is able to access many kinds of communication networks is disclosed. If the first electronic device receives a switching instruction at a time when a communication link and a data transmission have been established between the first electronic device and a second electronic device via a first communication network. Firstly, the first electronic device obtains an identification number of a third electronic device for use in a second communication network. Then, the communication link is established between the first electronic device and the third electronic device via the second communication network according to the identification number. Finally, the data is transmitted using the communication link between the first electronic device and the third electronic device via the second communication network, and disconnects the original communication link via the first communication link.