Abstract: To analyze differences among fruit economic characters of peach varieties in greenhouse and objectively evaluate the overall quality of their fruit, seventeen cultivars of peach in greenhouse were used as test material to determine twelve main economic characters of fruit in the mature period. Comprehensive evaluation function was constructed by principal component analysis to evaluate fruit quality of different cultivars, using relative variance contribution as weight factors. The results indicated that there were significant differences on fruit quality of the cultivars. The coefficients of variation of fruit flavor ( ratio of total soluble solids to acid) , fruit mass ( single fruit weight) and contents of fruit inclusion ( titratable acidity, vitamin C and soluble protein) were larger than other indices, and coefficients of variation of rate of pulp, fruit shape index and fruit uniformity were less.Total cumulative contribution of six principal components which extracted by principal component analysis reached 92.43%. The evaluation results which were mainly consistent with the measuring results of test showed that Chunxue fruit had a best overall quality, and the Xuri was the worst one.It could be concluded that principal component analysis could be performed to analyze the overall quality of peach fruit in greenhouse effectively.