Influencer marketing is a rapidly evolving digital strategy that harnesses the influence and credibility of social media personalities to promote brands, products, or services to specific target audiences. With the rise of platforms such as Instagram, Facebook and YouTube individuals have gained the ability to build significant followings, making them valuable partners for brands seeking authentic engagement with their consumer base. This chapter aims to explore how influencer marketing contributes to sustainable marketing efforts, focusing on the role influencers play in strengthening brand evangelism. The chapter is structured into sections that delve into the evolution of influencer marketing, the strategies influencers use to expand brand loyalty, and the challenges they face in promoting sustainable products. Additionally, it will examine the limitations of influencer marketing in driving consumer behavior towards sustainability and provide insights into the future of influencer marketing and brand evangelism in the context of long-term brand sustainability.