In order to improve the dynamic performance of the correlation tracker in a Space Solar Telescope, and to verify the feasibility and reliability of a beryllium mirror working in visible band,the tip-tilt mirror of the correlation tracker in the space solar telescope was studied. A Φ84 mm lightweight beryllium mirror was designed and fabricated. Beryllium powder was obtained by impact attrition technique, and the beryllium mirror blank was fabricated by hot isostatic pressing technique and mechanical processing. The nickel-phosphorus alloy layer was plated onto the substrate of beryllium mirror by electroless nickel plating, and the beryllium mirror was completed by optical processing. Surface testing results indicate that the surface figure errors of beryllium mirror are PV value of 0.114 λ and RMS of 0.012 λ (λ=632.8 nm), and the lightweight ratio is 43.68%. The results of surface figure error satisfy the technical requirements for the space solar telescope, which shows that beryllium can be used as mirror substrate materials of space astronomical instruments.