Butterfly hinge

The utility model relates to the technical field of hinge equipment, and provides a butterfly hinge which comprises a hinge piece, a fixing piece and an adjusting piece, shaft sleeves are arranged on the hinge piece at intervals, the head end and the tail end of the hinge piece are connected with a lock sleeve and a fixing sleeve respectively, a plurality of fixing grooves are formed in the lock sleeve, an annular groove is formed in the fixing sleeve, and the fixing piece comprises a fixing piece and a square-head screw. The square-head screw penetrates through the lock sleeve and penetrates through the shaft sleeve to extend into the fixing sleeve, a rectangular cavity capable of clamping the square-head screw is formed in the fixing piece, a fixing block capable of being matched with the fixing groove is connected to the fixing piece, a limiting block and an annular threaded sleeve are arranged on the adjusting piece, and the threaded sleeve is inserted into the fixing sleeve and is in threaded connection