This study aims to reveal the patterns of phenotypic variation in?Yulania?cultivar resources through a comprehensive evaluation of their phenotypic diversity characteristics, establish a scientific and practical evaluation system, screen ?cultivars with superior comprehensive traits, and provide a theoretical basis for germplasm enhancement and targeted breeding in?Yulania. Sixty-six?Yulania?cultivar resources were used as research objects, and 37 phenotypic traits were measured. Multiple statistical methods, including the coefficient of variation, diversity index, principal component analysis, membership function method, and cluster analysis, were employed to analyze phenotypic diversity and conduct a comprehensive evaluation. The results showed that the diversity index of the 66?Yulania cultivar resources ranged from 0.36 to 2.15 and the coefficient of variation ranged from 8.20% to 30.02%. Traits such as flower color, flower diameter, and leaf size exhibited high diversity indices. Among the 45 pairs of combinations of 10 quantitative traits, 34 pairs showed correlation coefficients significant at the 0.05 level, and most phenotypic traits exhibited mutual influence and promotion. Principal component analysis indicated that the top four principal components were overall growth of vegetative organs (PC1), relative flower size (PC2), floral structure (PC3), and pedicel development (PC4), collectively accounting for 88.42% of the cumulative contribution rate and covering the core morphological variations. This suggests that floral and plant architecture traits are key classification indicators. Using the membership function method, the F-values of the 66?Yulania?cultivar resources were calculated to range from -1.97 to 2.4, leading to the identification of 10Yulania?cultivars with outstanding comprehensive traits. Cluster analysis categorized the quantitative traits and cultivar resources into three groups each. The R-type clustering results visually demonstrated the associations among different quantitative trait indicators, consistent with the correlation analysis results. The Q-type clustering results divided the cultivars into three categories: Group I, comprising large-flowered arboreal types (63.64%); Group II, comprising transitional types (18.18%); and Group III, comprising small-flowered compact types (18.18%). This study provides a basis and methodology for the scientific evaluation and efficient utilization of?Yulania?cultivar resources.