In order to realize full aperture ultra-smooth polishing on the high order rotary symmetrical aspheric surface, the polishing head controlling algorithm is studied. The basic theory of ultra-smooth polishing technology and the computer numerical control machine mechanism are introduced. And the optical surface generating method is also descripted. Then, a kind of equal error recurrence algorithm is proposed which is used in solving dwell points and controlling polishing head path. And the path error is also analyzed. The polishing removal rate distribution of different positions is calculated and the dwell time mathematical solving model is established. Finally, an experiment for polishing an aspheric lens with a aperture of 150 mm and a asphericity of 116 μm is carried out on the self-research machine. The root-mean-square of surface roughness is reduced from 1.523±0.045 nm to 0.399±0.0238 nm. The result indicates that the algorithm described in this paper could improve the precision of asphere polishing path and the uniformity of the roughness distribution.