PURPOSE: A pharmaceutical composition, a cosmetic composition, and an antibacterial composition containing phthalimido peroxy carproic acid are provided to ensure excellent antibacterial property and to be used an agent for preventing or treating acne.CONSTITUTION: A composition for preventing or treating acne contains phthalimido peroxy carproic acid as an active ingredient. The composition prevents Propionibacterium acnes, Streptococcus pyogenes, Staphyllococcus aureus, or a mutant strain of Staphyllococcus aureus. An antibacterial composition contains phthalimido peroxy carproic acid as an active ingredient. The antibacterial composition has an antibacterial function against Propionibacterium acnes, Streptococcus pyogenes, Staphyllococcus aureus, or a mutant strain of Staphyllococcus aureus.COPYRIGHT KIPO 2013본 발명은 프탈이미도퍼옥시카프로익애씨드를 유효성분으로 함유하는 여드름 예방 또는 치료용 약학적 조성물, 화장료 조성물 및 항균용 조성물에 관한 것이다.본 발명에 따른 조성물은 독성이 낮고 여드름균에 대한 항균성이 우수하여, 여드름의 예방 또는 치료제로 유용하다.