Abstract: 【Objective】 To improve the application effect of chemical topping agent,and to compare the application effect of flupentine and cuhuawang cotton topping agent in southern Xinjiang. 【Methods】 In 2020,three cotton varieties Xinluzhong 37,Xinluzhong 70 and Xinluzhong 82 were selected and treated with the other three treatments: artificial topping (CK),flupentine application and Cuhuawang application. Two factor split plot design was adopted.The main plot was treated with two topping agents (flupentine combined with mepiquat,Cuhuawang molding agent combined with topping agent) and artificial topping (CK),and the sub plot was treated with three cotton varieties with three repetitions. 【Result】 The proportion of reproductive organs in the main treatments on September 3 was the highest,and that in the treatment of promoting chemical king was the lowest;the proportion of distribution coefficient of vegetative organs in the main treatments on September 3 was the highest when spraying Cuhuawang,and the lowest when spraying fluthrin.Comparison among main treatments:the seed cotton yield of Xinluzhong 70 under Cuhuawang treatment was the highest than that of other varieties,and the other two varieties were the highest under fluthrin treatment;Xinluzhong 37 had the highest lint percentage under the treatment of fluthrin,the other two varieties had the highest lint percentage under the treatment of Cuhuawang,and the three varieties under the treatment of artificial topping had the lowest lint percentage.The results also showed that the average length and breaking strength of the upper part of cotton fiber were the best,while the micronaire value and elongation were the worst. 【Conclusion】 The proportion of reproductive organs under fluthrin treatments on September 3 was the highest and that in the treatment of promoting Cuhuawang was the lowest the proportion of vegetative organs was opposite to that of reproductive organs.The seed cotton yield of Xinluzhong 70 under Cuhuawang treatment was the highest than that of other varieties,and the other two varieties were the highest under fluthrin treatment;Xinluzhong 37 had the highest lint percentage under the treatment of fluthrin,the other two varieties had the highest lint percentage under the treatment of cuhuawang,and the three varieties under the treatment of artificial topping had the lowest lint percentage.While the micronaire value and elongation were the worst;The results showed that the length uniformity and yellowness of cotton fiber were the best,and the specific strength was the worst;under artificial topping treatment,the micronaire value and elongation of cotton fiber were the best,while the average length of upper part,length uniformity and yellowness were the worst.