Abstract: 【Objective】 To study the effect of different dosage of humic acid on soil nutrients and cotton growth in Xinjiang cotton fields in the hope of providing scientific theoretical basis for the application of humic acid in Xinjiang cotton production. 【Methods】 The effects of CK(0 L/hm²,do not apply humic acid),T₁(Humic acid 225 L/hm²),T₂(Humic acid 450 L/hm²) and T₃(Humic acid 675 L/hm²) on soil nutrients, cotton growth, yield and quality were investigated through field plot experiment by setting four trial treatments. 【Results】 Humic acid effectively increased the availability of soil nutrients, and more binding sites were provided with the increase of humic acid dosage. When the application amount was 675 L/hm², the soil alkali-hydrolytic nitrogen content increased by 16.36%-25.66%, the available phosphorus content increased by 23.85%-32.22%, and the available potassium content increased by 20.15%-29.95%. The dry weight and leaf area of cotton increased gradually with the increase of humic acid dosage in the same growth period, and the promotion effect on plant height and stem diameter was the best when the application amount was 450 L/hm². Cotton yield increased by 18.60%, 27.44% and 10.61%, respectively. The cotton quality was improved, and the application amount of 450 L/hm² improved the cotton Micronaire grade. 【Conclusion】 Humic acid can improve the availability of soil nutrients, increase the content of soil available nutrients, promote cotton growth,application rate is 450 L/hm².