As the main metabolites of ginsenosides, 20(S, R)-protopanaxadiol (PPD(S, R)) and 20(S, R)-protopanaxatriol (PPT(S, R)) are the structural basis response to a series of pharmacological effects of their parent components. Although the estrogenicity of several ginsenosides has been confirmed, however, the underlying mechanisms of their estrogenic effects are still largely unclear. In this work, PPD(S, R) and PPT(S, R) were assessed for their ability to bind and activate human estrogen receptor α (hERα) by a combination of in vitro and in silico analysis.