The present invention relates to a composition for oral cavity having excellent antibacterial activity and, more specifically, to a composition for oral cavity comprising a Lactobacillus plantarum Ln1 strain (KCCM 12098P) as an active ingredient.COPYRIGHT KIPO 2020본 발명은 락토바실러스 프란타룸 (Lactobacillus plantarum) Ln1 균주(KCCM 12098P)를 유효성분으로 포함하는 구강용 조성물에 관한 것이다.