A kind of elimination image rotation subassembly based on integrated shafting design,and its optical alignment method are described in the paper.This subassembly can apply to airborne photoelectricity radar,vehicle-borne panoramic sighting telescope and other optical system,and solves the problem of optical system image rotation.The subassembly uses integrated shafting design,that is,the bearing inner ring channel is machined directly on the main shaft,and the main shaft,bearing balls,and bearing outer ring and cage are integrated assembly.At the same time,the prism components can be adjusted in the main shaft on one-dimensional direction,which can overlap prism optical axis and mechanical axis.It can make the optical axis rotation precision of elimination image rotation subassembly prism achieving ±12″through the alignment method introduced in this article.Compared with other elimination image rotation systems,it has characteristics of high precision,strong stability,small volume,light weight,simple structure and easy to align.