Forty-three annual Citrus aurantium grafted seedlings from Chongqing, Sichuan, Hunan, Jiangxi and other main producing areas were collected, and the plant height, rootstock diameter, scion diameter, root length, root diameter, lateral root number, root breadth, branch number, branch length, green leaf number, leaf length, leaf width, thorns and other indicators were measured. Through the K-cluster analysis of SPSS 19.0 software, the classification standards were obtained. Combined with the production practice, plant height, scion diameter and branch number were taken as the quality classification indexes of C. aurantium seedlings(annual grafted seedlings), and three classification standards were established. If it does not meet the three-level standard, it is unqualified seedling and cannot be used as seedling. It is suggested to use the first and second level seedlings in production.