Abstract: Studying the light environment of in intercropping alley of jujube and winter wheat could provide references for winter wheat cultivation. To ascertain the variation characteristics of light environment, the authors set intercropping plots with jujube planted by 1.0 m×4.5 m, 1.0 m×2.5 m, 0.5 m×4.5 m. Li-6400 Portable Photosynthesis System, LAI-2000 plant canopy analysis meter, and light sensor LI-190 were used to measure the photosynthetic parameters and photosynthetically active radiation (PAR) of the alley at different growth stages of winter wheat. The method of PAR space- time window was used to calculate the size of saturated PAR space-time window of the winter wheat canopy at different growth stages. The results showed that winter wheat in maturation stage had higher light saturation point (LSP) and lower light compensation point (LCP) than the winter wheat in filling stage. In intercropping plots with jujube planted by different modes, the size of saturated PAR space-time window of the winter wheat canopy was in an order as: 1.0 m× 4.5 m＞ 0.5 m× 4.5 m＞ 1.0 m× 2.5 m. In conclusion, considering the photosynthetic demand of winter wheat in the alley, jujube planted by 1.0 m× 4.5 m was the best intercropping mode of jujube and winter wheat in southern Xinjiang basin.