Multi-network communication method and multi-network communication system

The invention discloses a multi-network communication method and a multi-network communication system. The method comprises the following steps: when the multimode terminal receives a call request initiated by a target terminal to a first call object in a first network, calling a call mapping relationship between the first call object and a call object in a second network, and determining a second call object corresponding to the first call object in the second network based on the call mapping relationship; initiating a call request to a second call object through the multi-mode terminal; when it is determined that the call request of the multi-mode terminal is successful, first voice information corresponding to the first call object is sent to a second call object, second voice information corresponding to the second call object is obtained, and the second voice information is sent to the first call object; and the third voice information of other calling objects except the second calling object is sent to