To control membrane mirror figure, the physical model of Stretched Membrane with Electrostatic Curvature (SMEC) was established. The control principle of electrostatic shaping was introduced according to the balance between electrostatic force and resulting force formed by membrane deformation and the complex shaping process of SMEC. Then, taking the trisection circularity electrode for an example, the distribution characteristic of electric potential in the electrostatic field was analyzed, namely, the expression of potential function in the electrostatic field was deduced by Laplacian equation. And then, by combining the difference equation with electric potential expression, the numerical solutions of electrostatic force in single electrode mode and trisection circularity electrode mode were disposed. Finally, the calculated figure was compared with the ideal paraboloid and comparison shows that more accuracy would be achieved by multi-electrode control. The simulation and experimental results indicate that the force distribution in multi-electrode mode is more even than that in singe electrode mode, and membrane mirror of 180 mm in diameter can acquire the maximum 0.001 094 8 mm deformation controlled by a same size single electrode under voltage of 10 000 V. The system can work steadily and safely for a long time, while the symmetry of membrane mirror is preferably.