Background: Ginseng is Chinese traditional herbal medicine, and the ginsenoside Rg 3 is the main bioactive ingredient for the anti-tumor effect. However, there is no study on pharmacokinetics (PKs) of ginsenoside Rg 3 and its main metabolite after oral ginsenoside Rg 3 in tumor-bearing plasma. The aim of this study was to investigate the PK profiles of ginsenoside Rg 3 and ginsenoside Rh 2 after oral administration of pure ginsenoside Rg 3 were administered, and compare the difference of the PK profiles between normal and Walker 256 tumor-bearing rats. Materials and Methods: The concentrations of two ginsenosides in plasma were determined by using a simple and rapid high-performance liquid chromatography. All the rats were divided randomly into two groups (Walker 256 tumor-bearing and normal groups). Each group received oral administration of 50 mg/kg ginsenoside Rg 3 . Results: The results showed that ginsenoside Rh 2, possibly as a glycosylation hydrolysis product of ginsenoside Rg 3, were found in plasma after oral administration of ginsenoside Rg 3 to rats. Ginsenoside Rg 3 had shown better absorption than ginsenoside Rh 2, whether the oral administration of ginsenoside Rg 3 , normal rats showed better absorption than tumor-bearing rats. Discussion and Conclusion: The PKs properties of the ginsenoside Rg 3 and ginsenoside Rh 2 differed between tumor-bearing rats and normal rats, including area under the plasma level/time curve and concentration maximum (P < 0.05).