The invention discloses an edge cutting device. The edge cutting device comprises an upper cutting knife set and a lower cutting knife set, the upper cutting knife set and the lower cutting knife set each comprise a hollow screw (1), each hollow screw (1) is provided with at least two cutting knives (2), and the cutting knives (2) of the upper cutting knife set correspond to the cutting knives (2) of the lower cutting knife set in a one-to-one manner; the hollow screw (1) in the upper cutting knife set is arranged on an upper lifting support (3), and the hollow screw (1) in the lower cutting knife set is arranged on a lower lifting support (4); and a transverse rod (5) is further arranged above the upper cutting knife set and provided with a plurality of laser knife setting mechanisms (6), the laser knife setting mechanisms (6) can move on the transverse rod (5), and lasers are emitted to the two hollow screws (1). According to the edge cutting device, as the multiple cutting knives are arranged, when edges of films are cut, the two side edges can be cut into small stripes, the working amount is greatly saved, and the working time is greatly shortened.