The mature silkworms of Bombyx mori L. have recently been regarded as a potential health supplement due to gainingtheir edibility for humans by a newly-developed steaming method. Therefore, this study was conducted to investigate theeffects of steamed and lyophilized mature silkworm powder (SMSP) on skin pigmentation and melanogenesis. Orally administeredSMSP significantly and dose-dependently reduced abnormal pigmentation caused by ultraviolet B (UVB) on the murinedorsal skin. SMSP also showed a potential anti-melanogenic efficacy in modulating UVB-induced melanogenesis. Takentogether, SMSP was identified as a potential candidate for a novel anti-melanogenic agent, which showed hypo-pigmentingefficacy against UVB-induced melanogenesis in vivo when administered orally.