A portable electronic apparatus and a touch detecting method thereof are provided. In the method, a touch is detected by a touch screen of the portable electronic apparatus. Then, whether the touch is located in an edge area of the touch screen is determined. If it is determined that the touch is located in the edge area of the touch screen, the touch time during which the touch continues and no other touch is detected by the touch screen is accumulated, and whether the accumulated touch time exceeds a preset time is determined. If the accumulated touch time exceeds the preset time, related information of the touch is removed from an event triggered by the touch until the touch ends.