Connecting piece of steel pipe column and prefabricated square pile and combined supporting stand column

The utility model discloses a connecting piece of a steel pipe column and a prefabricated square pile and a combined supporting stand column, and belongs to the field of construction structures. The connecting piece comprises a pile cap, a rigid connecting pipe and a pile end connecting assembly. The steel pipe column and the prefabricated square pile can be coaxially connected through a connecting piece; the pile cap sleeves the top of the prefabricated square pile and is fixedly connected with a pile top end plate of the prefabricated square pile through the pile end connecting assembly, the rigid connecting pipe is tightly inserted into a bottom middle hole of the steel pipe column, and the bottom of the steel pipe column is fixedly welded to the top face of a pile cap top plate. The prefabricated square pile and steel pipe column combined supporting stand column is adopted to replace a conventional cast-in-situ bored pile and steel latticed column combined supporting stand column, the prefabricated square