Abstract: 【Objective】 To ascertain photosynthetic characteristics and grain-filling rate and yield of different winter and spring wheat cultivars under extremely-late sowing. 【Method】 The suitable sowing period of winter wheat is from 20th to 30th in September, and the planting period of this test is October 31, with a delay of 31-41 days sowing. Under ultra-late sowing conditions,the randomized block designed field experiment was compared the difference between photosynthetic characteristics, grain-filling rate and yield of different winter and spring wheat cultivars in the field. 【Result】 The leaf chlorophyll content, net photosynthetic rate, transpiration rate and stomatal conductivity of winter and spring wheat varieties varied among different cultivars. The yields of Xindong 41 and Xinchun 6 were higher than other cultivars, which were 60.2 and 58.1, 33.1 μmol/(m²·s) and 32.5 μmol/(m²·s), 10.22 m mol/(m²·s) and 10.41 m mol/(m²·s), 0.33 mol/(m²·s) and 0.36 mol/(m²·s). The peak rate of the maximum grain-filling rate of spring wheat cultivars occurred 18-20 days after, while winter wheat occurred 15-17 days after. The yields of Xindong 41 and Xinchun6 were relatively high, ranging from 7,812.3 kg/hm² to 7,935.6 kg/hm². The number of high-yielding spikes was 431.7×10⁴/hm²~475.2×10⁴/hm², the number of spikes was 31.6-36.3, and the number of thousands of grains weight was 51.7~52.8 g. 【Conclusion】 Comprehensively considering all the factors, Xindong 41 and Xinchun 6 are more suitable for ultra-late winter sowing in northern Xinjiang.