Abstract: [Objective and Method]Chemical treatment of slow-release mepiquat chloride from cotton coating seed, which has practical significance in saving cost and increasing benefit, is one way of simplified cultivation of cotton. This paper analyzed the effect of slow-release mepiquat chloride by using different doses of mepiquat chloride in coating seed. It involved in the influence of slow-release mepiquat chloride on cotton growth, agronomic and economic characters, and so on. [Mesult]The results showed that slow-release mepiquat chloride of middle and high dose had good effects on avoiding spindling of cotton before topping, and its function was similar to foliar application of mepiquat chloride in regulating the growth and agronomic characters of cotton.Slow-release mepiquat chloride has little effect on yield. [Conclusion]Chemical manipulation of slow-release mepiquat chloride can replace the foliar application of mepiquat chloride before topping.