In recent years, the increasing environmental awareness has changed consumers’ interest and purchase intentions toward eco-friendly products. Brands aim to create lasting impressions in consumers’ minds by promoting their eco-friendly products through social media, particularly via Instagram influencers. The purpose of this study is to identify the factors affecting the purchase intention of eco-friendly products. The analysis was conducted on a convenient sample of 347 individuals over the age of 18 who use cosmetic products in Turkey. Influencer attractiveness and congruence positively influence attitudes toward green cosmetics, while influencer credibility did not show a significant effect. Furthermore, brand awareness, brand associations, brand loyalty, and brand quality positively affect brand equity, which in turn positively impacts purchase intention. A positive attitude toward green cosmetics strengthens purchase intention. Based on the hypotheses tested in this study, it was found that influencer attractiveness and congruence positively affect consumers’ attitudes toward green cosmetics, while influencer credibility does not have a significant impact. Additionally, brand awareness, brand associations, brand loyalty, and brand quality and credibility were found to positively affect brand equity. Finally, brand equity was found to have a direct positive impact on the purchase intention of green cosmetics. Implications for the academicians and retailing sectors were discussed.