Abstract This paper reports a case of humeral head defect after operation of proximal giant cell tumor of humerus，and humeral shaft fracture with nonunion was treated with reverse total shoulder arthroplasty. With the healthy side as the template combined with 3D printing technology, the reverse total shoulder joint prosthesis was customized, and the pre-reserved tuberosity bone mass was bundled with the nodule indwelling hole of the prosthesis and the structural bone graft was used to reconstruct the rotator cuff. The good function of shoulder joint after operation suggests that we should pay attention to the design of prosthesis before operation and the reconstruction of rotator cuff function during operation.