Based on the high resolution imaging spectrometer data of OMIS I we performed a simulative calculation from 6S. Relation between radiance at satellite level and variety of zenith observation angle was discussed and correlative error in the retrieve of surface reflectance was analyzed, simultaneously. The results show that there are spectral properties about this effect, it is sensitive in the strong scattering regions and the major absorption channels by atmosphere;On the other hand, the brightness of targets and the flight elevation decides this effect. Based on this analysis a primary correction strategy was given