Background: 20(S)-protopanaxadiol (20(S)-PPD), one of the main active metabolites of ginseng, performsa broad spectrum of anti-tumor effects. Our aims are to search out new strategies to enhance anti-tumoreffects of natural products, including 20(S)-PPD. In recent years, fasting has been shown to be multifunctional on tumor progression. Here, the effects of fasting combined with 20(S)-PPD on hepatocellular carcinoma growth, apoptosis, migration, invasion and cell cycle were explored. Methods: CCK-8 assay, trypan blue dye exclusion test, imagings photographed by HoloMonitorTM M4,transwell assay and flow cytometry assay were performed for functional analyses on cell proliferation,morphology, migration, invasion, apoptosis, necrosis and cell cycle. The expressions of genes on proteinlevels were tested by western blot. Tumor-bearing mice were used to evaluate the effects of intermittentfasting combined with 20(S)-PPD. Results: We firstly confirmed that fasting-mimicking increased the anti-proliferation effect of 20(S)-PPDin human HepG2 cells in vitro. In fasting-mimicking culturing medium, the apoptosis and necrosisinduced by 20(S)-PPD increased and more cells were arrested at G0-G1 phase. Meanwhile, invasion andmigration of cells were decreased by down-regulating the expressions of matrix metalloproteinase(MMP)-2 and MMP-9 in fasting-mimicking medium. Furthermore, the in vivo study confirmed thatintermittent fasting enhanced the tumor growth inhibition of 20(S)-PPD in H22 tumor-bearing micewithout obvious side effects. Conclusion: Fasting significantly sensitized HCC cells to 20(S)-PPD in vivo and in vitro. These data indicated that dietary restriction can be one of the potential strategies of chinese medicine or its activemetabolites against hepatocellular carcinoma.