Disclosed are a device and a method for sending or receiving a reply or forward message in a mobile communication terminal. When a user selects a reply or forward menu in relation to a specific original message, the title of the original message is extracted and set as the title of a reply or forward message. The number of messages having the same title as the original message is determined to generate an indication of the number of replies or forwards. According to the user's selection of the reply menu or the forward menu, a title header including a prefix indicating a reply or a forward and the indication of the number of replies or forwards is generated and inserted into a reply or forward message input window. A recipient of the reply or forward message can easily perceive whether the received message is a reply or a forward. The recipient can also perceive the number of replies exchanged between the two mobile communication terminals or the number of times the original message has been forwarded.