A method for transmitting a message containing both common content to be transmitted to a plurality of receiving mobile communication terminals and specific content to be transmitted to a specific receiving mobile communication terminal includes displaying, when in a message writing mode, a message writing window including a first writing area and a second writing area, writing messages in the first writing area and the second writing area, inputting a telephone number of the receiving mobile communication terminal to which the message written in the second writing area is to be transmitted, combining the messages written in the first writing area and in the second writing area, and transmitting the messages to the receiving mobile communication terminal.