A method of controlling the operation of a mobile terminal having a multimedia data service capability is disclosed. The method initially includes establishing a call connection to a base station if a multimedia data service request is made by a mobile terminal user to receive multimedia data. Upon establishing the call connection, the mobile terminal sends a multimedia data service request signal to a base station and receives the corresponding multimedia data for a first predetermined period of time. Then, it disconnects the call connection and stops providing electric power to a signal receiving/transmitting part of the terminal after receiving a confirmation signal responding to the play-back period it has calculated earlier. Finally, it plays-back the received data for the play-back period. By using the present invention, an unnecessary connection fee can be eliminated, and the power being supplied to the mobile terminal while playing-back the data can be efficiently saved.