Abstract: Twenty five samples of garlic collected from different geographical areas were studied by FT-IRS and their fingerprints were established. Comparative study on the FTIRS data was made by applying the chemometrical methods of principle component analysis (PCA) and clustering analysis. It was shown by the results that: ① chemical composition and relative contents (in %) of the components were found to be different for samples from different geographical areas or populations, which furnished as a base for differentiation of sources of garlic; ② as shown by PCA and clustering analysis, the 25 samples could be classified into 4 groups, leaving 2 samples (25# and 4#) locating far apart from the 4 groups; and the grouping was related significantly with the geographical and environmental factors, e.g. the hindrances of gene exchange due to geographical spaces; populational environments of the plantation area of garlic and etc.