Disclosed are a system and a method of controlling an audio output in a mobile communication terminal, and more particularly to a system and a method of controlling an audio output of mobile communication terminal, wherein when a broadcasting channel is changed, an audio signal of the mobile communication terminal is not outputted for a preset time or in an ineffective channel from which a broadcasting does not come through.The mobile communication terminal having a television function according to an embodiment of the invention is characterized in that when a broadcasting channel is changed, a video signal is outputted and at the same time an audio signal is not outputted by turning off the amplifier for a preset time, and when the preset time lapses, the amplifier is turned on and thus the audio signal is outputted.