Abstract: An optical system of UV limb panoramic imager was designed by using panoramic annular lens (PAL) and relay lens, the central wavelength was 360 nm, the waveband was 10 nm, the field of view was 360(70.9～73.3), the focal length was 5 mm, and the relative aperture was 1:3.3. The method of improving the uniformity of image illumination was studied against the large field of view of the optical system. Optimization and analyzsis were performed using CODE V and ZEMAX software. The design result shows that the RMS radius of disc of confusion of spot diagram is less than half of the pixel, 80% of energy is enclosed in a pixel, the MTF is 0.72@38.5 lp/mm, the f- distortion is less than 0.4%, the uniformity of image illumination is 91%. The design results satisfy the requirement of the specifications, the volume is small, and suitable to application in space atmosphere sounding. It indicates that the optical design method of UV panoramic imager is feasible, and the design method can be used in other wavebands, it is instructional for designing the panoramic imager.