Abstract: Solar radiation is one of the main agroclimatic resources. Three wave ranges of the spectrum in the solar radiation are infrared, visible and ultravioled light radiations. As infrared radiation provides with thermal effect and ultraviolet radiation provides with biological and chemical effect, their quantity and characteristics greatly affect the growing, yielding and quality of crops. Thus, using the 30-year solar radiation data from 9 solar radiation stations in Xinjiang, the solar radiation at 100 odd stations is calculated in this paper. The proportions of infrared and ultraviolet radiations in total solar radiation are defined, i. e., infrared radiation occupies 0.50 and ultraviolet only 0.07. The annual infrared radiation is 2549～3170 MJ.m-2.a-1 and ultraviolet radiation 356～444, their distribution laws show that infrared and ultraviolet radiations in south part of Xinjiang are more than that in north part. The maximum values of infrared and ultraviolet radiations occur in Lop Nur Lake region in Hami, they are 3170 MJ.m-2.a-1 and 444 MJ.m-2.a-1 respectively; the minimum values of which appear in Junggar Basin, they are 2549 MJ.m-2.a-1 and 356 MJ.m-2.a-1 respectively.
The annual variations of infrared and ultraviolet radiation are in an unimodal pattern, the maximum value in winter is 2.79 MJ.m-2.d-1; the maximum value of ultraviolet radiation in summer is 0.86 MJ.m-2.d-1 and its minimum value in winter is 0.34 MJ.m-2.a-1 infrared and ultraviolet radiations in Kelamayi in the west Junggar Basin and in the west part of Tarim basin are 2548. 7 MJ.m-2.a-1, 178. 4 MJ.m-2.a-1; 2856.5 MJ.m-2.a-1 and 200.0 MJ.m-2.a 01 respectively.
The infrared and ulatraviolet radiations increase 9. 88 MJ.m-2.a-1 and 1.19 MJ.m-2.a-1 respectively with the rising of elevation per 100 m.

Key words: infrared radiation, ultraviolet radiation, distribution law