A planetary bevel gear automatic limited slip differential includes five portions that are a main differential, a planetary bevel gear controller, a left drive axle shaft, a right drive axle shaft, and clutches. The planetary bevel gear controller includes an outer control unit and an inner control unit, the outer control unit includes four planetary bevel gears on an outer layer and a bevel gear fixed on a housing, and the inner control unit includes inner planetary bevel gears on an inner side and two bevel gears which have the same parameters and are meshed with the planetary bevel gears. The bevel gears are fixedly connected with outer rings of two overrunning clutches, respectively, and inner rings of the overrunning clutches and the right drive axle shaft are connected together by splines.