The present invention provides a composition for inhibiting melanogenesis, which comprises two extracts isolated from the stems ofCinnamomum subavenium- linderanolide B and subamolide A. These two components contain anti-tyrosinase ability, so as to inhibit melanogenesis in cells or subjects and to be applied in whitening cosmetology.本發明提供一種抑制皮膚色素沉著之組合物,其係包含兩種由香桂(Cinnamomum subavenium)莖部分離出之化合物-林得羅內酯B(linderanolide B)和速巴莫內酯A(subamolide A)。該兩種化合物具有抗酪胺酸酶能力,可抑制細胞或個體之黑色素生成,並用於美白化妝之用途。