The utility model relates to a button device for a pipe-shaped lock. A spacing sheet is mainly arranged in an inner cover plate; the upper and the lower walls of an inner rotating shaft is provided with a positioning hole and a spacing slot; a transmission cylinder is also sheathed in the inner rotating shaft; the front side of the transmission cylinder is connected with a button; the button protrudes at the middle part of an inner handle; the upper and the lower sides of the middle part of the transmission cylinder are provided with a through hole and a punch hole which are opposite; a brake piece which can move from top to bottom is arranged between the through hole and the punch hole; the upper side of the brake piece is provided with a bulge, and the lower side is provided with a push rod. Thereby, the phenomenon that people are locked out of a door can be avoided.