Objective: This paper studied the effect of irrigation quota and application cycle on the growth of the cotton and its yield under the condition of mulched drip irrigation. Method: Different irrigation quota and cycles were designed. The soil moisture was monitored before and after the irrigation. The physiological index such as the budding amount and cotton height were measured at different stages of cotton growth. Result: The study shows that cotton's height is unsusceptible to the irrigation cycle in a state of low irrigation quota. With the irrigation quota increasing, the cotton's height is higher and higher; when the irrigation quota is certain, with the irrigation cycle increasing, the cotton's height is decreasing. When the irrigation quota is 3300 m 3/hm 2 and the irrigation cycle is 8d, the number of the bolls are the most, it is helpful for improving the cotton's production; when the irrigation cycle is 10d, the bolls are the fewest. Conclusion: When the irrigation quota is 5100 m 3/hm 2 and the irrigation cycle is 10d, it's helpful for the cotton's buds to appear early. When the irrigation quota is 4688 m 3/hm 2 and the irrigation cycle is 8d, the production is the highest and the comprehensive benefits is the most.
