This study aims to evaluate the phenotypic diversity of Yulania cultivar resources through a comprehensive evaluation of their phenotypic diversity characteristics， establish a practical evaluation system， identify elite cultivars with superior comprehensive traits， and provide a theoretical basis for germplasm enhancement and targeted breeding. Sixty-six Yulania cultivars were used to examine 37 phenotypic traits. Phenotypic diversity and comprehensive evaluation were conducted using multiple statistical methods， including the coefficient of variation， diversity index， principal component analysis， membership function method， and cluster analysis. The results indicated a range of diversity indices （0.36 to 2.15） among qualitative traits and pseudo-qualitative traits， and coefficients of variation （8.20% to 30.02%） among quantitative traits. Correlation analysis of 10 quantitative traits revealed 42 pairs with significant （P<0.05） or extremely significant （P<0.01） correlations out of 45 combinations. For example， leaf length was significantly positively correlated with leaf width but significantly negatively correlated with tepal number. Principal component analysis extracted four principal components， including overall growth of vegetative organs， relative flower size， floral structure， and pedicel development， collectively accounted for 88.446% of the cumulative variance. This suggests that floral and plant architecture traits are key diagnostic indicators. Using the membership function method， the F-values of the 66 Yulania cultivar resources ranged from -1.97 to 2.40. Ten cultivars with outstanding comprehensive traits， including Frank's Masterpiece， Helmer， and Star Wars. Cluster analysis categorized the quantitative traits and cultivar resources into three distinct groups each. The R-type clustering results visually demonstrated trait associations， aligning with the correlation analysis. Q-type clustering 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 systematic evaluation and efficient utilization of Yulania cultivar resources.