The cotton field cover treatments including biodegradable mulch film(BD) and the common mulch(PE) were set up in 2017,Shihezi,Xinjiang to study the degree of degradation of biodegradable mulch film and effects on soil temperature,cotton canopy density,yield and quality under drip irrigation conditions.The economic effects were analyzed.Results showed that the film surface began to degrade after 60 days of BD coverage,and the degradation rate of cotton harvest was 75.71%.The PE was not degraded during the whole growth period,and the normal loss of film quality was 4.70%.The soil temperature at the four stages of cotton including seedling,bud,flowering and boll opening under BD treatment was 1.80,2.32,2.26,and 0.91℃ lower than that under PE treatment,respectively.There was no difference in the degree of canopy density between the BD and PE at 58 d.The density was completed at 87 d.The growth rate of BD canopy was 6.36% faster than that of PE.The plant height,the number of fruit branches,and the weight of single bolls of BD were all lower than that of PE,but the number of effective bolls per plant of BD was 0.1 higher than that of PE.BD reduced production by 55.8 kg/hm2 compared with PE.There was no difference in cotton fiber quality.The net income of BD decreased by 1 012 yuan/hm2.In production,BD can be used to replace the common film and improve the residual film pollution problem to a certain extent,but the price and function is still needed to be further optimized.