The application discloses a path generation method for treating an aspheric surface in a gasbag polishing way. The path generation method comprises the following steps: establishing a contact model ofa polishing tool and an aspheric surface workpiece; generating a spiral curve formed by sequentially connecting a plurality of polishing paths according to a searching point by point algorithm; and adjusting the distance on the polishing path in the radial direction through the contact model. Based on the polishing path generated according to Archimedes screw, physical and uniform covering of thesurface of the workpiece is realized on the aspheric surface.