Abstract: Phenotypic diversity of 12 important agronomic characters include leaf and nut phenotype and quality for 90 Chinese chestnut cultivars from 10 provinces were analyzed using nested design variance analysis and cluster analysis methods. The results showed：(1) There were significant differences for 12 agronomic traits of chestnut among and within populations，indicated that there existed a wide range of variation in the two levels；(2) The average variation coefficient of leaf and nut phenotype and quality traits were 7.7%，4.4% and 6.8%，respectively，showed that genetic stability of nut phenotype traits was higher than the other two traits；(3) The average of phenotypic differentiation coefficient among populations were 23.42%，which were less than the variation within populations（76.58%），showed that the variation within populations was the main source of variation；(4) Ten populations of chestnut were divided into 4 categories by using the minimum distance cluster analysis，indicated the differences of phenotypic diversity of chestnut existed in different geographical population.

Key words: chestnut, local cultivars, agronomic traits, phenotypic diversity