Looking at the current cultural phenomena, Korean-style beauty is being favored by Indonesians, seeing this, Wardah chose Ayana Jihye Moon as a Korean celebrity as a brand ambassador. The positive image and appeal of Ayana attracts the attention of the public so that it is expected to have a good influence on interest in buying Wardah cosmetic products. The purpose of this study is to find out how much influence the credibility of Ayana Jihye Moon in Wardah advertisements have on buying interest in followers of her Instagram account. The research method used in this research is explanatory quantitative research. Respondents in this study are Ayana Moon Instagram followers with a total of 400 respondents who are calculated using the Slovin formula. The results of this study indicate that there is an influence between the brand ambassador's credibility on buying interest of 0.489 or 48.9%. While the remaining 51.1% of Ayana Moon followers' buying interest is influenced by other factors not examined in this study, i.e job differences, socioeconomic, age, gender, hobbies and consideration of Wardah's halal guarantee products from the MUI.