A method and an apparatus f preventing transmitting message input error in a mobile communication terminal are provided. When another event is generated while the transmitting message is being inputted, character input keys are inactivated and an event window is displayed. It is checked whether an ENTER key is pressed while the event window is displayed. If the ENTER key is pressed, the event window and an icon notifying generation of the event are closed. Accordingly, a user of the mobile communication terminal can recognize the generation of the event and prevent transmitting message input error after identifying the generated event.