Abstract: A hair clipper includes a main body and a cutter head assembly. A motor is provided in the main body, and an eccentric shaft of the motor protrudes from a front end of the main body. The cutter head assembly includes a heat dissipation device, a stationary blade and a movable cutter assembly. The heat dissipation device includes a heat dissipation plate and a mounting structure, and a front side of the mounting structure is provided with a vertically communicated accommodation cavity. The stationary blade is fixed on a bottom plate of the mounting structure. The movable cutter assembly includes a torsion spring, a movable cutter base and a movable blade, the movable blade is fixed on the movable cutter base, a rear end of the movable cutter base is provided with a connection structure, the movable cutter assembly is disposed in the accommodation cavity.