There are usually large low order aberration in the output beam of high energy laser system. It’s possible to compensate the defocus and astigmatism by a set of spherical concave mirrors and cylinder concave mirrors. According to the cantilever beam theory, a cylinder deformable mirror has been designed. By finite element simulation the structure and size parameters of the deformable mirror are optimized, and the deformation stroke reaches 19 μm, the residual peak to valley value is less than 1.4 μm. A prototype has been produced according to the optimal result. The surface precision and the relationship between deformation and driver voltage are measured by a Fizeau interferometer. The experimental results show that by controlling the displacement of the piezoelectric actuator, this deformable mirror structure can produce the desired parabolic surface, and stroke reachs 11 μm.