Abstract: Scientific classification of quantitative traits is of great significance to variety description and specificity determination in maize DUS test.By individual measurement of DUS quantitative traits in 272 maize hybrids from 2018 to 2019,the variation of DUS quantitative traits in maize in Guizhou was statistically analyzed.The distribution law of each trait was analyzed based on K-S test, and the classification and correlation analysis of each quantitative trait were also conducted.The results showed that the variation coefficient of the number of the primary lateral branch of tassel and ear height of plant was larger in Guizhou area, while the variation coefficient of fruit cluster diameter was the smallest.The 12 traits showed normal distribution or nearly normal distribution, and isometric division was further performed according to the classification rule of range greater than or equal to 2 folds LSD_0.05.The correlation between the length of the main axis above the branch of the highest position of tassel and the lateral branch length of tassel or the length of the main axis above the branch of the lowest position of tassel was high.To reduce the workload, the traits of main shaft length above the highest branch and the lowest branch of tassel could be removed, and the traits of main shaft length above the lowest branch of tassel could be retained.