A study was conducted on thirty cassava germplasm accessions through evaluating 40 phenotypic traits. Genetic diversity analysis and systematic phenotypic evaluation were assessed by applying diversity indices， correlation analysis， and principal component analysis， leading to the identification of excellent cassava germplasm resources. Results showed that the genetic diversity index （H′） of 24 qualitative traits ranged from 0.393 to 2.056， with broad-sense heritability （H²） varying between 91.16% and 100.00%. The highest H′ value was observed for the color of young stems， while the lowest was for the situation of rotten roots. Twelve traits exhibited H′ values greater than 1， including color of the first fully expanded leaf， color of the top unexpanded tender leaves， and shape of the tuberous roots. For the 16 quantitative traits， the coefficient of variation （CV） ranged from 12.17% to 61.66%， the genetic diversity index from 0.7614 to 2.0883， and the broad-sense heritability from 84.19% to 99.58%. The highest H′ value was observed for the harvest index， and the lowest was for the number of lobes and leaflets. With the exception of the number of lobes， 15 traits （including plant height， fresh root starch content， and leaf area） all have genetic diversity indices greater than 1. This indicates that the 30 cassava types are diverse and have rich genetic diversity. Plant height was significantly correlated with fresh tuber weight per plant， the color of the inner and outer bark of the main stem， and the color of the tuberous root flesh. Principal component analysis extracted 13 principal components， with a cumulative contribution rate of 82.23%. Among them， plant height， stem diameter， the color of the top unexpanded leaves， and fresh tuber weight per plant had relatively large contribution rates. Stepwise regression analysis identified seven independent traits， including the color of the top unexpanded tender leaves and the distribution of tuberous roots， which significantly affected the comprehensive traits of cassava. The excellent germplasm resources ranked in the top 10 were selected by the comprehensive evaluation method of membership function， including H588， GR6， and GR3. Cluster analysis divided the 30 germplasm resources into four major categories： Group Ⅰ comprised high-yield and high-starch genotypes； Group Ⅱ included hybrid breeding materials with medium plant height， concentrated tuberization， high harvest index， and abundant flowering； Group Ⅲ consisted of erect plant types with high yield potential； and Group Ⅳ encompassed low-branching genotypes with compact plant architecture and moderate starch content. These results can provide valuable insights for efficient exploration and utilization of cassava germplasm resources and support future breeding of new varieties.