The invention discloses an oblique tongue oblique breaking device comprising a bracket. The bracket is provided with a working tabletop, the working tabletop is provided with a conveying device, and one side of the conveying device is sequentially provided with a display device, a feeding device, a clamping device, a cutting device and a discharging device. The oblique tongue oblique breaking device is simple in structure and can be universally used for various products; an oblique tongue can be cut off automatically simply and conveniently, and thus manpower and material resources are saved;a device replacement fixture needs to be simple and convenient, production is facilitated, and the working efficiency is improved.