This study examines the effect of cosmetic certification marks on consumer behavior. The underlying objectives of this study are threefold. First, it explores whether the certification mark inserted into the cosmetic package—such as marks denoting quality assurances, ethical practices (specifically, pertaining to animal testing), and recycling packaging—affects consumer responses. Second, it investigates whether a higher number of certification marks leads to heightened positive consumer responses. Third, it analyzes the potential moderating effect of consumers’ certification mark knowledge on the relationship between certification marks and consumer responses. In the pretest, certification marks with higher recognition were selected as stimuli, and a survey involving a total of 550 male and female consumers was conducted. The collected data were analyzed through ANOVA and post-hoc tests. The findings of this study confirm a significant difference in consumer responses to products based on the certification marks inserted in the cosmetic packaging. Compared to clusters without a certification mark, groups with two or more certifications (recycling certification + ethics certification, recycling certification + quality certification, recycling certification + ethics certification + quality certification) exhibit significant consumer responses. Second, more certification marks did not result in an increase in positive consumer responses. Third, a moderating effect of consumers’ cosmetic certification knowledge on the certification mark-consumer response relationship was not found. The findings of this study have implications for developing product promotion strategies that leverage cosmetic certification marks as a marketing tool.