Abstract: In order to realize the transverse super-resolution imaging with a telescope optical system, a two-dimensional polynomial function phase pupil filter with a high strehl ratio was designed, and its improvement for the light distribution around the focal point of the optical imaging system was demonstrated. The result of the theory analysis shows that, when the filter is added into the system, the system transverse optical resolution is increased 1.33 times, and the Strehl ratio is 0.75 time as much as that of the system without this pupil filter. The performance of two-dimensional polynomial filter was compared with the other typical phase pupil filters, including the three-zone, the four-zone and the one-dimensional polynomial phase filter. The comparison results show that the Strehl ratio of the two-dimensional polynomial filter is the highest in these filters, and the transverse super-resolution ratio of this filter is next only to that of the four-zone filter. But the Strehl ratio of the four-zone filter is too low to be applied into the telescope. The influence of the incident field angle on the imaging results of the telescope optical system was also be studied, and it was found that the super-resolution effect of the system is better when the field-of-view is no more than 4.