The invention belongs to the technical field of animal husbandry, and particularly relates to a fermentation device for animal husbandry excrement treatment. In view of the problem of incomplete fermentation, presented is the following scheme, namely, the fermentation device comprises a fermentation box, a motor is arranged on the outer wall of the top of the fermentation box, a rotating rod is arranged on an output shaft of the motor, cross rods distributed at equal intervals are arranged on the outer wall of one side of the rotating rod, crushing and stirring blocks distributed at equal intervals are arranged on the two sides of the outer wall of each cross rod, each crushing and stirring block is of a sickle-shaped structure, the inclination directions of the crushing and stirring blocks located on the two sides of the rotating rod are opposite, and a stirring ring is arranged on the outer wall of one side of each cross rod. The device is provided with the cross rods, the crushing and stirring blocks, the stirring rings, rotating plates, fixed plates, first crushing blocks, second crushing blocks, springs and stirring floating balls, the crushing and stirring blocks are each ofa sickle-shaped structure and can crush excrement, the excrement and fermentation liquor can be mixed more comprehensively, different vortexes can be generated by the stirring rings of different specifications and sizes, and the mixing effect of the excrement is improved.