Prefabricated building main body structure

The invention discloses a prefabricated building main body structure, and relates to the technical field of constructional engineering structures. The prefabricated building main body structure comprises an independent foundation; at least one layer of floor slabs is fixedly arranged above the independent foundation; a supporting structure is arranged under each layer of the floor slabs; a roof frame structure is fixedly arranged above the top layer of the floor slabs; the floor slabs comprise a plurality of combination beam plates; the supporting structure of each layer comprises a plurality of square pipe columns; tenon pipes connected with the combination beam plates in an inserting manner are arranged on the square pipe columns; a stairway is arranged between every two vertically adjacent layers of floor slabs; the combination beam plates comprise four-corner components; steel beams are fixedly connected between the adjacent four-corner components; the upper edges of the steel beams are spaced from the to