Background: Mountain ginseng (Panax ginseng Meyer), which belongs to Araliaceae family, grows naturally in the mountains of Korea. It is highly valued owing to its enhanced pharmacology effects such as immunostimulating, antioxidant, anti-cancer and antiaging activity. An alternative to accessing the sparse mountain ginseng therapy benefits is by tissue-cultured roots of mountain ginseng. The aim of this study is to evaluate the effect of water extract of cultured roots of mountain ginseng (CRMG) and specifically its major compound ginsenoside Re (Re) on melanin synthesis in α-MSH-stimulated mouse melanoma B16BL6 cells (B16). Materials and Methods: Cell cytotoxicity was evaluated trough a comparative study using normal human dermal fibroblast (HDF) and B16. Then, α-MSH-stimulated B16 cells were analyzed, using melanin and tyrosinase activity assay. Tyrosinase gene expression was evaluated trough reverse transcription polymerase chain reaction analysis and quantitative PCR analysis. Finally, an in silico docking study was performed. Results: The study demonstrated that CRMG and Re were non-toxic compounds and significantly reduced tyrosinase activity and melanin content in B16 cells. Re decreased the mRNA expression of tyrosinase and other melanin synthesisrelated genes in B16 cells. In addition, in silico docking studies showed that Re had stronger interaction with tyrosinase compared to control drug arbutin due to its higher binding affinity. Conclusion: Taken together, our results suggest that CRMG and Re possess potential anti-melanogenic activities and may be used as antimelanogenic cosmeceutical agents.