Abstract: 【Objective】 The aim of this study is to clarify the response of equal nitrogen applied with urease inhibitor Acetohydroxamic acid (AHA) on cotton growth, development, yield, and quality mulched drip irrigation in order to provide a theoretical basics for efficient and reasonable nitrogen management of cotton. 【Methods】 Field experiments were conducted by using Xinluzao 42 under four kinds of AHA addition ratios (the addition amount was 0% of the nitrogen application amount (U), the addition amount was 1% of the nitrogen application amount (U + UI_1%), the addition amount was 2% of the nitrogen application amount (U + UI_2%) and the addition amount was 5% of the nitrogen application amount (U + UI_5%). 【Results】 Compared with U, AHA significantly improved the physiological growth of cotton at flowering stage, bolling stage and full boll stage. Plant height, stem diameter, leaf area index, net photosynthetic rate, transpiration rate and stomatal conductance in the key period (flowering stage, bolling stage and full boll stage) was U + UI_2% > U + UI_1% > U + UI_5% treatment. The seed cotton yield of U + UI_1%, U + UI_2% and U + UI_5% treatments was significantly higher than that of U by 4.59%, 9.18% and 4.65%, and there was significant difference between U + UI_2% and other treatments (P < 0.05). There was no significant difference in cotton quality among different treatments (P > 0.05). Correlation analysis showed that there was the largest positive correlation between net photosynthetic rate of leaves and seed cotton yield, and there was a negative correlation between single boll weight and seed cotton yield. 【Conclusion】 The U + UI_2% treatment of urea combined with 2 % nitrogen application AHA shows the best performance in cotton growth, physiology and yield, which is the best choice for high stability nitrogen application of drip irrigation cotton. The results will provide data support and theoretical reference for efficient management of drip irrigation cotton nitrogen fertilizer in Xinjiang.