Apparatus and method for controlling operation in portable terminal having a multimedia function

An apparatus and a method for controlling the operation of a portable terminal having a multimedia function are provided to reduce current consumption of the portable terminal, and to reduce software errors occurring when a controller controls a multimedia process because it is unnecessary for the controller, which controls mobile communication functions, to control a multimedia process, which controls multimedia functions. A multimedia processing module(170) performs a multimedia function when a control mode is in a sleep mode. A controller(130) switches the sleep mode into an activation mode, if a predetermined key is input in the sleep mode, to output a deactivation signal used to deactivate the multimedia processing module(170). If the predetermined key is input in a deactivation mode of the multimedia processing module(170), the controller(130) outputs an activation signal used to activate the multimedia processing module(170) and then switches the deactivation mode into the sleep mode.