The invention provides a method for constructing an immune healthy synovial sarcoma xenograft mouse model; the method comprises cultivating a generation P0, to be specific, resuscitating a tumor tissue block of a synovial sarcoma patient stored in a liquid nitrogen environment, then transplanting the tumor tissue block into an immunodeficient mouse under a sterile condition, and pretreating a micewith normal immunity by cyclosporine; culturing a generation Px, to be specific, inoculating the tumor tissue block, grown in a mouse from any of the generations P0 to Px, into the mouse pretreated with cyclosporine to form a generation Px mouse; and culturing a generation Py, to be specific, inoculating a synovial sarcoma tumor tissue block, grown in a mouse from any of the generations Px to Py-1, into the mouse with normal immunity until tumor tissues grow in the mouse, so that culturing of the generation Py is completed. The invention solves the problem that the traditional PDX (patient-derived xenograft) model has no immune system, provides an in-vivo model for the research on tumor immunotherapy, and widens the application range of the PDX model.