A new diamond micro-displacement magnifying mechanism using eight cross-spring flexural pivots was presented for light beam acquisition, tracking and pointing in space optical communication. The piezoelectric ceramic was taken as the actuator, and the cross-spring flexural pivots as the centralized flexural elements. Every two pivots were set in one axis, and the coaxial set of two pivots on each corner of the diamond configure could reduce the axis draft and improve the rigidity and stability of the mechanism. Through analyzing the operation principle, the magnifying ratio and the sensitivity of the mechanism were derived. According to the stiffness model of the cross pivots, the theoretical stiffness of the displacement mechanism was deduced. Finally the displacement mechanism was modeled by finite element method and its kinematics, statics and dynamics were simulated. A prototype was established and tested. Some characteristic parameters were derived, such as the structure stiffness and the eigen frequency of the mechanism. The test results show that the magnifying ratio is 1.905 with the error of 2.2%, the stiffness is 18.21 N/mm with the error of 0.2% and the eigen frequencies is 8.8 Hz with the error of 5%. The experimental data verify the feasibility and effectiveness of proposed design and show that the mechanism is suitable for high precise spatial micro-displacement fields.