Abstract: In order to investigate the relationship between free amino acid and cigarette taste,the contents of 17 free amino acids in 15 brands of cigarette were determined with ultrasonic extraction and amino acid analyzer,and the data were processed with principle component analysis and cluster analysis.The results showed that the method could be used in the comparison and classification of cigarettes of different tastes,and the proportion distribution of various amino acids reflected fairly well the characteristics of different brands of cigarettes,which could be served as a reference in cigarette classification and irritation and abundance evaluation.