For determining similarity of chemical fingerprint, similarity measures were presented. A method including three indexes (i.e. elasticity of peak number, homostasis of proportion among peaks and homostasis of peak area) was proposed to evaluate the performance of the measures on different aspects. According to the three proposed indexes, six different measures were evaluated with chemical fingerprints simulated by computer. The results indicated that cosine of the angle is much suitable for assessing the fluctuation of proportion between the peaks. The matching degree of peaks is very sensitive in detecting the variation of number of small peaks. The Euclidean distance has preferable integral measurement capability. The actual chemical fingerprints of Shenmai injection were used to check the correctness of the above conclusion from simulation experiments, and the results showed it accords with reality. It could be concluded that the proposed method could be used for selecting the meausres for determining the similarity of chemical fingerprint.

Key words: chemical fingerprint, CHINESE DRUG, QUALITY CONTROLS