This study compares the use of profanity expressions in Japanese and Indonesian languages on the Twitter social media platform by examining profanity expression forms based on six categories, namely genital terms, excretory terms, animal terms, anatomical terms, imbecilic terms, and general terms, as well as eight reference categories for profanity expressions, namely situations, animals, supernatural beings, objects, body parts, kinship, activities, and professions. Using a descriptive contrastive method combined with a qualitative approach as the research design, this study analyzed two Twitter accounts containing profane expressions, namely the @Hanadayo0903 account (Japanese) held by Hana Kimura and the @JeromePolin account (Indonesian) owned by Jerome Polin. Hughes (1991) and Wijana and Rohmadi"s ( 2006) ideas on the types and allusions of profane expressions are used in this study. Hana Kimura"s account discovered five reference categories for profanity terms, activity references, animals, circumstances, occupations, and things. However, the Jerome Polin report discovered three profanity phrases, namely mental disability, animals, and general. These findings suggest that profanity expressions in Japanese revolve around activity references, such as imperative words for "death". In contrast, profanity expressions in Indonesian tend to focus on mental disabilities, such as "stupid".