In one aspect, the present invention relates to a composition for blackening hair, preventing whitening of hair, preventing or treating melanin-lowering diseases, which contains siRNA comprising the nucleotide sequence of SEQ ID NO: 1 or SEQ ID NO: 2 as an active ingredient. According to one aspect of the present invention, the hair-related industry can be developed and the welfare of related consumers can be improved. [Selection] Figure 1本発明は、一側面において、配列番号1又は配列番号2の塩基配列からなるsiRNAを有効成分として含む毛髪の黒化用、毛髪の白化防止用、メラニン低下性疾患の予防及び治療用組成物に関し、本発明の一側面により毛髪関連産業の発展を図り且つ関連消費者の福祉を増進させることができる。【選択図】図1