The increasingly fierce business competition causes producers to have a marketing strategy that can attract consumer buying interest. Cosmetic products are considered to have great potential, especially for halal cosmetic products. The concept of Islamic branding and the concept of marketing using celebrity endorsers is very attractive to consumers' buying interest. There is still a lack of consumer understanding about halal standards for a product, causing producers to have to provide clear information for the products to be sold. This study aims to determine the effect of Islamic branding, celebrity endorser and product knowledge on consumer purchasing decisions for Wardah cosmetics. The research method used is a quantitative method. The population in this study were students of the Faculty of Islamic Religion, Ibn Khaldun University, Bogor with a total sample of 88 respondents. The data analysis method used is SEM-PLS. The results showed that; 1) The Islamic branding variable has a positive but not significant effect on purchasing decisions, 2) The celebrity endorser variable and product knowledge have a positive and significant effect on purchasing decisions. Even though Wardah products already have a halal certificate and use muslimah advertising stars, they are still not enough to influence purchasing decisions. Wardah can improve marketing by adding more Islamic themes.