A touch screen device and an operating method thereof are provided. The touch screen device is operated by touching a touch screen and moving a touch while the touch is maintained on the screen. A detector detects a touch point and a moving trajectory, and a controller selects a user command based on the detected touch point and moving trajectory. Then, when the user releases the touch, the controller executes the user command. User commands are classified and stored in a storage device and then executed by the controller based on operation modes associated with the device. A variety of user commands may be executed even though not all the menus are not displayed on the screen at once. Further, a user may cancel an erroneously entered user command quickly and easily.