To investigate the pharmacodynamic basis of ginseng for preventing nausea and vomit induced by chemotherapy (CINV). Ginseng was first extracted using ultrapure water to gain water extract, and then the water extract was treated by ethanol to obtain alcohol precipitation component, or by resin using water and ethanol (60%, 90%) eluent to acquire water rinse component, 60% ethanol rinse component and 90% ethanol rinse component, respectively. The fingerprints of these different components were established using HPLC. The effect of water extract of ginseng and the different components on the intake of kaolin and feed was conducted in a cisplatin-induced pica model of rats. Finally, the correlation between the intake of kaolin and feed and the peak area in the fingerprints was analyzed for preliminary determination of the pharmacodynamic basis of ginseng for preventing CINV. The water extract of ginseng and 60% ethanol rinse component significantly reduced the intake of kaolin, compared with the model group, there were significant differences (P?0.01)；Alcohol precipitation component，water rinse component and 90% ethanol rinse component，compared with the model group, there were significant differences (P?0.05). This result indicated that the effective components were included in the 60% ethanol rinse component. The coefficients of spectrum-effect relationship demonstrated that the pharmacodynamic basis of ginseng was related with chromatographic peaks of X1、X3、X4、X5、X6、X7、X8、X9、X10、X11, associated with ginsenosides of Rg1、Re、Rb1.