Hollow jack and hollow object dismounting and mounting device

The invention relates to a hollow jack and a hollow object disassembling and assembling device which are used for solving the technical problem that the disassembling and assembling work efficiency of parts such as shaft sleeves and bearings is low. The hollow jack comprises an annular cylinder body, an annular plunger and an annular top sleeve. The annular cylinder body is provided with a center channel penetrating in the axial direction of the annular cylinder body, and the annular plunger is connected into the annular cylinder body in a sliding mode and can move in the axial direction of the annular cylinder body. The number of the annular top sleeves can be multiple, the annular top sleeves are detachably arranged on the annular plunger in an alternative mode, and the annular top sleeves have different inner diameters. According to the size of an object, one of the annular ejector sleeves is selected to be detachably arranged on the annular plunger so as to push the object. The shaft sleeve can be disasse