Instagram as a social media platform has gained prominence as the medium of influencer marketing practices targeting consumers of beauty products, yet little is known about source characteristics affecting Instagram opinion leadership resulting in consumers’ purchasing behavior. Thus, this work examines effects of Instagram influencers’ attributes (credibility, attractiveness, innovativeness, and sense of humor) on their perceived opinion leadership and its subsequent impacts on consumers’ behavioral intentions. The research also analyzes complementary moderating effects of parasocial relationship and social identity reinforcing behavioral implications of social media opinion leadership. Empirical results from 202 Instagram followers reveal that credibility, innovativeness, and sense of humor exert positive influence on perceived opinion leadership which subsequently enhances levels of positive word-of-mouth, purchase, and loyalty intentions. Besides, social identity strengthens positive impacts of opinion leadership on consumers’ word-of-mouth and purchase intentions. Thus, the findings not only contribute to the theory of opinion leadership, but have beneficial implications enabling beauty brands to develop effectual social media marketing communication strategies.