Disclosed is a method of performing satellite communication in a synchronous or asynchronous mobile terminal containing a satellite communication module (SCM) having a satellite antenna for performing direct communication with a satellite, thus allowing communication in areas where there exists no land communication network as well as allowing land radio communication. The method includes a first step of interfacing between the satellite communication apparatus and the land communication apparatus such that predetermined signals are transmitted/received between the satellite communication apparatus and the land communication apparatus; and a second step of performing the satellite communication according to the signals transmitted/received between the satellite communication apparatus and the land communication apparatus through the interfacing.