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Because of higher labor costs and comparative effectiveness decline in China, cotton planting areas have been declined quickly.Wheat, barley, rape and cotton double cropping system will be key cotton planting types in Yellow River and Yangtze River cotton planting areas.Shifting the growing season later may allow the crop to develop under more bloom favorable weather patterns and escape late season low temperature.The objectives were to determine the affects of late planting on agronomy traits of different mature cotton cultivars.The data of plant growth, earliness, yield and fiber quality as agronomy traits were collected from five genotypes planted at April 25 (early sowing) and May 25 (late sowing) in 2012 and 2013 year.The results showed that plant height, branch numbers and boll numbers were significantly affected by cultivars and planting date.Date of the first square was significantly shorten and harvested rate befbre frost (HRBF) was significantly decreased for five different mature cotton cultivars in late sowing.The HRBF was 29.9% for Lumianyan 28, 18.8% for CCRI 41 and 25.8% for CCRI 45 were significantly lower than that of 78.3% for CCRI 50 and 81.0% for CCRI 74 in late sowing.Date of the first flower, date of the first open boll of Lumianyan 28, CCRI 41 and CCRI 45 were significantly prolonged compared with that of CCRI 50 and CCRI 74 in late sowing.Number of node first sympodial branch of Lumianyan 28,CCRI 41 and CCRI 45 was significantly higher than that of CCRI 50 and CCRI 74 in late sowing.Yield and yield-related traits were significantly decreased for spring cotton varieties, Lumianyan 28, CCRI 41 and CCRI 45, but for summer cotton varieties, CCRI 50 and CCRI 74 Yield and yield-related traits were less affected by late sowing.Fiber quality was less affected for five cotton varieties.Fiber length, fiber strength and uniformity index were not significantly affected by late sowing.Fiber elongation and yellowness were significantly increased in late sowing.Therefore, in double cropping condition, the short season cotton is an appropriate alternative to grow faster and improve earliness, yield and fiber quality under properly increasing plant density in compensation reduced yield in late planting.