Purpose: This study was performed to determine the inhibitory effect of Soyosangagamhwajae(SYG) on melanin synthesis in B16F10 mouse melanoma cell. Methods: The Inhibitory effects of Soyosangagamhwajae(SYG) on melanin synthesis were determined by in-vitro assay. To elucidate inhibitory effects of SYG on melanin synthesis, we determined the melanin release in B16F10 cell. And to investigate the action mechanism, we assessed the gene expression of tyrosinase, TRP-1, TRP-2. PKA, $PKC{eta}$ in B16F10 cell. Results: 1. SYG significantly inhibited melanin-release in B16F10 cell. 2. SYG significantly inhibited mushroom tyrosinase activity in vitro. 3. SYG significantly suppressed the expression of tyrosinase in B16F10 cell. 4. SYG significantly suppressed the expression of TRP-1, TRP-2 in B16F10 cell. 5. SYG significantly suppressed the expression of PKA, $PKC{eta}$ in B16F10 cell. Conclusion: From these results, it may be concluded that SYG has the antimelanogenetic effect.