Commelina communis Ledeb is a widely used medication for the treatment of antidiabetic, antioxidant and hypoglycemic agent in Korea. Alpha-melanocyte stimulating hormone (${alpha}$-MSH) is a major factor to stimulate melanin synthesis in the skin. The purposes of this study was to investigate the inhibitory effects of extract from Commelina communis Ledeb (ECC) on ${alpha}$-MSH-stimulated melanogenesis in B16F10 cells. ECC suppressed melanin synthesis and intracellular tyrosinase activity in B16F10 cells or ${alpha}$-MSH-induced B16F10 cells in a dose dependent manner. In study on the melanogenic protein expressions, it had especially influence on expressions of tyrosinase and tyrosinase-related protein (TRP-1). Tyrosinase and TRP-1 expressions were gradually decreased in a dose-dependent. Additionally, the extract also decreased the ${alpha}$-MSH-induced over-expression of tyrosinase and TRP-1. This results show that the anti-melanogenic activity of ECC is correlated with the suppression of tyrosinase and TRP-1 protein expressions in B16F10 cells.