Abstract: Compared to conventional optics, binary optical elements have some unique advantages. A reflective and diffractive hybrid telescope with an aperture of 25m was designed, with two binary optical elements as its objective and eyepiece. The dispersed spot size and MTF of the telescope meet the requirements. The high order diffractive lenses take the place of conventional diffractive lenses to improve the performance of the system, and the telescope achieves a broader bandwidth. The results show that the modified system can provide almost diffractionlimited imaging quality within the range of single-band, multi-band or continuous coverage.