The invention relates to the construction field. The processing method of a pre-stress square pile includes the steps that: firstly, bar sheathing, wherein, a main octagonal reinforced bar is sheathed in an inner octagonal spiral hoop bar according to a hole position and then a main tetragonal reinforced bar is sheathed in a tetragonal position in a tetragonal hoop bar and the two ends are lockedtightly by anchorages; secondly, tensioning, wherein, the main reinforced bar is tensioned by sections in a tensioning platform to 105 percent of the tension and then anchoring is carried out; thirdly, casting, wherein, the concrete casting is conducted in compound die after the inspection of tension and when the strength of the concrete meets the requirements, the reinforced bar is released and the unwanted main reinforced bar is cut; fourthly, finishing operation is carried out. Compared with the similar processing method, the method of the invention does not need pre-cast reinforced cage, and the bar sheathing can be directly conducted in the tensioning platform; the hoop bar is a spiral bar, thus having convenient installation but no breaking end, saving time and labor and having no need for wielding. The processing method of the invention can be used for pre-making solid pile or hollow pile in various sizes, thus increasing the anti-cracking strength and the limit bending moment of the pile body and prolonging the service life to 50 to 100 years.