Abstract: After several years experiments and extensive investigations on late planted winter wheat after cotton harvested,the canopy structure and its influence on yield were analysed systemati-cally. The results showed that the optimum LAI was about 5.5 to 6.0 ,the vertical distribution of leaf area was uniform and most of the ears were from main stalk.The length of green leaf area extending period,dry matter production and partitioning condition were also analysed.Based on the results,and optimum pattern for high yield of the late planting winter wheat after cotton harvested was that high density of stalk,suitable varieties and appropriate fertilizer and water supply.