The invention provides a differential mechanism shell; the upper end and the lower end of the hollow internal side wall of the left differential mechanism shell are respectively provided with a spherical surface; the left differential mechanism shell is internally provided with a hole used for installing cross shafts respectively in the transverse direction and in the longitudinal direction; the transverse cross shaft hole is vertically crossed with the longitudinal cross shaft hole; the right differential mechanism shell is an end cover; the circumference of the right differential mechanism shell is connected with the circumference of the left differential mechanism shell by a bolt; the differential mechanism shell improves the production efficiency, reduces the market malfunction rate, increases the bearing capability and reduces the manufacture cost simultaneously.