This systematic literature review examines the growing influence of social media influencers over traditional media in shaping public opinion. Analyzing 26 Scopus-indexed studies published between 2020 and 2025, the review finds that influencers build strong trust and engagement through parasocial relationships, emotional storytelling, and niche relevance, often outperforming traditional media in influencing attitudes and behavior. While influencers act as powerful cultural intermediaries in digital communication, the study also highlights ongoing challenges such as misinformation, ethical concerns, and commercialization, offering important implications for research, marketing practice, and media policy.