The present invention relates to a portable terminal having a touch screen and a function control method thereof, wherein when a function is executed, a touch screen having a display unit for displaying a function execution screen and a touch panel for detecting a drag generated on the function execution screen; and , When a control interaction guide display request is detected while displaying a function execution screen, at least one control interaction guide for guiding a control command that can be executed on the function execution screen is displayed on the function execution screen, and when a drag is detected on the touch screen, A control unit that detects a control command corresponding to drag and controls to perform a function corresponding to the control command, and stores a control command that can be executed on the function execution screen and a control interaction guide that can be displayed on the function execution screen under the control of the control unit. A portable terminal including a memory and a method for executing functions thereof are provided. According to the present invention, when a function is executed in a portable terminal, a control interaction guide is displayed on the function execution screen, thereby guiding a control command that can be executed on the function execution screen for a user of the portable terminal. Accordingly, in using the portable terminal, there is an advantage in that the user's convenience is improved.