Abstract:To advance the breeding of new sweet cherry varieties and enhance the conservation and utilization of germplasm resources, this study employed correlation analysis, principal component analysis, and cluster analysis to evaluate and investigate 12 external and 4 internal quality indicators of fruits in 35 sweet cherry varieties (lines). The results revealed that the predominant fruit shape was oblate, with a flat fruit and a concave fruit apex. The Simpson indices for these three descriptive traits were 0.700, 0.561, and 0.573, respectively, indicating a rich diversity. Among the 13 quantitative traits, the coefficient of variation (CV) was lowest for the edible rate (3.35%), and highest for the abnormal fruit rate (95.00%). High CVs were also observed for fruit stalk separation force (30.82%), solid acid ratio (28.05%), flesh weight (26.65%), and fresh core weight (26.03%), reflecting substantial genetic differentiation. Single fruit weight was significantly positively correlated with fruit flesh weight and edible rate; While the solid acid ratio was significantly positively correlated with fruit juice pH and negatively correlated with titratable acid content. Cluster analysis categorized the sweet cherry cultivars into four distinct groups based on fruit quality attributes. Group A exhibited the lowest average titratable acid content and the highest average edible rate; Group B showed the highest average fruit stalk thickness and hardness, with lowest average total soluble solid content and pH value; Group C, which include only one variety, Black Pearl, had the largest single fruit weight and abnormal fruit rate with smallest fruit stalk separation force and group D presented the highest average total soluble solid content and pH value, along with lowest average abnormal fruit rate and edible rate. Collectively, 'Regina', 'SJ-54', and 'Royal Lee' with high composite scores, were identified as superior parents with potential application in sweet cherry breeding programs.