The present invention relates to a multi-network integration security and authentication method, comprising the following steps: S1. providing a multi-network integration module, same being simultaneously connected to the Internet and a telecommunication network; and S2. the multi-network integration module carrying out, based on the identity authentication of telecommunication and by means of a channel of a telecommunication network, secure information exchange with a user terminal. In the present invention, by means of a channel of a telecommunication network, secure information exchange is carried out, based on the identity authentication of telecommunication, with a user terminal, wherein the whole process does not require the participation of a third-party cloud end. The present invention avoids the defects in the existing technology, and has the advantages of being secure, reliable and difficult to attack artificially.