The utility model discloses a broaching clamp for a wheel slot of a wheel disc of a gas turbine engine and relates to a tool for processing, positioning and clamping the wheel slot of the wheel disc of the gas turbine engine. The broaching clamp is designed against the problem that a clamp integrating positioning, mounting and clamping into a whole is absent for broaching the wheel slot of the wheel disc of the gas turbine engine. A key which is in positioning connection with a key slot of an indexing table of a machine tool is arranged in the key slot of a positioning disc of a circular disc-shaped lower boss, a first T-shaped bolt connecting component which is in detachable connection with the indexing table of the machine tool is arranged in a first counter bore on a circular disc-shaped upper boss, a second T-shaped bolt connecting component which is in detachable connection with the indexing table of the machine tool is arranged in a second counter bore on the circular disc-shaped lower boss, a cylindrical pin which is in positioning connection with the wheel disc of a product is arranged in a cylindrical pin mounting hole of the positioning disc, a rhombic pin which is in positioning connection with the wheel disc of the product is arranged in a rhombic pin mounting hole of the positioning disc, the lower end of a screw rod is in threaded connection with the positioning disc, the upper end of the screw rod penetrates out of a gland bush, a cylindrical pad is in threaded connection with the gland bush through a screw, and a retaining nut is screwed on the screw rod. The broaching clamp is suitable for processing the wheel slots of the wheel discs of the gas turbine engines in various specifications.