In order to realize space-based remote sensing for river, lake and ocean environment monitoring and break through the key technology of hyperspectral imaging system, based on the Ritchey-Chrétien (R-C) Cassegrain folding reflector telescope, we designed a front telescope system with a working altitude of 600 km, a working spectral band of 450-900 nm, a full field of view of 2.9°, a system focal length of 400 mm, the optical speed of F/4 and effective control of aberration and chromatic aberration of adding three-piece correction mirror to control the field of view is designed. The initial structural parameters of the front telescope system are solved according to the primary aberration theory, and the secondary mirror blocking ratio of the front telescope system is designed to be 0.35, and the simulation and optimization design are carried out in ZEMAX software. The system performance analysis shows that more than 80% of the energy of the imaging spot is concentrated within 12 μm.The maximum aberration is 0.78% and the maximum magnification chromatic aberration is 1.26 μm.The RMS (Rate-Monotonic Scheduling) radius of spot at all fields of view and wavelengths in the point column diagram is less than 2.6 μm (Airy radius is 3.3 μm). At the Nyquist frequency of 25 lp / mm, the MTF (Modulation Transfer Function) values of each spectral section in all fields of view are greater than 0.8.All the above evaluation indexes meet the performance requirements of hyperspectral imaging system © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.