Optical synthetic aperture technology is a key technology in space optics. In order to make theoretical and application research on this technology in depth, an installment and adjustment system of high precision synthetic aperture has been designed. The paper mainly introduces the installment and adjustment system of primary mirror in optical system. The primary mirror is composed of three segment mirrors. Via the installment and adjustment system of each segment mirror, the primary one is synthesized. Segment mirror clamping mode is analyzed and clamping force is calculated, the maximum and minimum clamping forces are drawn, which make the surface figure deformable within the requirement range. An integrate analysis of the deformation of surface figure of segment mirror is also conducted and confirmed, which is caused by clamping force and temperature fluctuation and should be controlled below the wave length of 1/20. The segment mirror installment and adjustment system consists of 3 DOF translation platform and 2 DOF angle adjusting part. 2 DOF angle adjusting is realized by high precision screw thread pair driving flexible hinge, which ensures not only the simplicity, but also the stability and precision of the system as well. Experimental research is conducted on the flexible hinge and proves the rationality of the system. According to the test of the prototype, the translation resolution of the segment mirror installment and adjustment system reaches 0.2μm, the angle resolution reaches 0.5", which successfully satisfies the requirement of the synthetic aperture technology.