The invention provides an opening/closing operation device used for a shaver cutter, and relates to the technical field of shaver; the technical problem to be solved is the opening/closing operation of the cutter; the opening/closing operation device comprises a body shell which is pivotally connected with a cutter, a main button and a buckle which are arranged on the shell; the middle part of the main button is provided with a button hole which is internally provided with a small button; the left side and the right side of the lower side of the main button are provided with a lower convex bar and a lower inclined surface; two sides of the lower part of the small button are provided with a lower inclined surface; the small button is internally provided with a small button spring; the left side and the right side of the front end of the buckle are provided with a hook used for locking the cutter; the base of the hoop is provided with a buckle front inclined surface which is corresponding to the lower inclined surface of the main button so as to be used for opening the hoop; the middle part of the buckle is provided with two buckle locking blocks which are corresponding to the lower convex bar of the main button so as to lock the main button; a buckle rear inclined surface which is corresponding to the lower inclined surface of the small button is arranged between the two buckle locking blocks so as to open the two buckle locking blocks; the opening/closing operation device has the advantages of leading the opening/closing operation of the cutter to be much safer, more reliable, briefer and more convenient.