The invention discloses a cutting device with a good fixing effect for bearing machining. The cutting device comprises a box body. Supporting plates are fixedly connected to the two sides of the bottom of an inner cavity of the box body. A clamping plate is arranged on the top of each supporting plate. Containing grooves are formed in the tops of the supporting plates and the bottoms of the clamping plates. First electric telescopic rods are fixedly connected at the positions, located on the back portions of the supporting plates, of the two sides of the bottom of the inner cavity of the box body. By means of the cutting device, due to cooperation of the box body, the supporting plates, the clamping plates, the containing grooves, the first electric telescopic rods, limiting holes, limiting rods, a sliding groove, a first sliding rod, sliding blocks, second electric telescopic rods and supporting plates, the purpose of the fixing effect of the cutting device for bearing machining is achieved, the phenomenon that the fixing effect of the cutting device for bearing machining is poor, and consequently the cutting position is not flat is avoided, the bearing machining efficiency is ensured, resource waste is avoided, the requirements of the market are met, and the problem that the fixing effect of the cutting device for bearing machining is poor is solved.