Abstract: In the highly accelerated near ultraviolet (NUV) irradiation simulation tests on the vulnerable materials for spacecraft, it is essential to control the uniformity of the NUV irradiation to improve the effectiveness of the test simulation and the accuracy of the test results. In this paper, the Xenon lamp is used as the NUV irradiation source, while the condenser, the integrator, and the reflector or the filter are used to realize a highly accelerated NUV irradiation with quite good uniformity. At the same time, the collimating mirror and the divergent mirror are designed to realize a high acceleration rate on a suitable large irradiation area. The NUV simulation with an irradiance of 15SC on an area of ϕ300 mm, or an irradiance of 24SC on an area of ϕ180 mm can be realized, with a uniformity better than 95%.