A touch operation processing method and a terminal device is presented. The method includes detecting a touch operation of a user, which starts from a border of a screen display area to the screen display area, and using the first point touched by the touch operation in the screen display area as a starting point; and performing, according to the touch operation, reduction processing on an operation interface displayed in the screen display area, where one edge of an operation interface after the reduction processing includes the starting point. Therefore, the demand is met that the user triggers, by one hand, reduction processing on the operation interface and perform a selection operation on an arbitrary position in the entire screen display area of the terminal device when the user holds the terminal device with a large screen with one hand on it.