This paper carried out diversity evaluation on the 6 agronomic traits of plant height，leaf length，leaf width，pseudostem length and diameter，bulb weight of the 81 accessions of garlic germplasm resources collected from Sichuan area；and at the same time conducted correlation analysis combined with altitude by
principal component analysis and clustering analysis. The results showed that the garlic resources in Sichuan area had rich genetic variation. The variable coefficient of the above 6 agronomic traits were 19.13%-73.43%，among which the variable coefficient of the bulb weight was as high as 73.43%. The 6 agronomic traits could be integrated into 3 principal components and the cumulative contribution rates accounted for 87.804 6%. The first principal component represented the plant type，the second and the third principal components represented bulb weight. Based on the principal component analysis，the 81 accessions of garlic resources were classified into 4 groups at the level of Euclidean distance 169.8 by clustering analysis. As important resources，group Ⅱ was the important resource for breeding one-clove garlic variety，and group Ⅲ was important resource for high-yield variety. The altitude was significant positive correlation with garlic bulb weight，while was extremely significant negative correlation with plant height and pseudostem length.