This study provides a comprehensive overview of micro-influencer marketing, analyzing the characteristics of influencers and the mechanisms of their impact. A systematic review of 74 studies involving 95 research institutions and over 12,000 samples was conducted, covering 2091 citing articles. The research integrates insights from computer science, information science, communication, culture, psychology, sociology, education, business, and management to outline the distinct features of micro-influencers, including performable authenticity, affinity through consistency and transparency, musical and artistic media talent, and competitive individual traits. The study synthesizes antecedents of trust and attachment mechanisms in influencer theory, focusing on the impact of self-expressive products on audience purchase intention. The findings highlight that followers' pursuit of self-branding, driven by self-consciousness, social consciousness, credibility, and social presence, significantly influences the impact of self-expressive products on the audience's purchase intention. The research contributes to micro-influence marketing theory by integrating mechanics, offering practical implications for micro-influencers, and suggesting future research agendas. The study also explores the characteristics of micro-influencers, their followers, and the mechanisms driving their impact on user behavior. It discusses the connections between changes in these attributes or mechanisms and subsequent economic conditions, brand marketing strategies, and follower psychology. The research identifies key journals and research focuses in the field, emphasizing the importance of interdisciplinary research. The study highlights the role of micro-influencers in shaping consumer behavior, particularly in the context of social media, and their impact on brand marketing and consumer perceptions. The research also examines the influence of micro-influencers during the pandemic, emphasizing their role in disseminating social awareness and health information. The study concludes that micro-influencers play a crucial role in shaping consumer behavior and brand marketing strategies, and future research should focus on further exploring the mechanisms underlying their influence.This study provides a comprehensive overview of micro-influencer marketing, analyzing the characteristics of influencers and the mechanisms of their impact. A systematic review of 74 studies involving 95 research institutions and over 12,000 samples was conducted, covering 2091 citing articles. The research integrates insights from computer science, information science, communication, culture, psychology, sociology, education, business, and management to outline the distinct features of micro-influencers, including performable authenticity, affinity through consistency and transparency, musical and artistic media talent, and competitive individual traits. The study synthesizes antecedents of trust and attachment mechanisms in influencer theory, focusing on the impact of self-expressive products on audience purchase intention. The findings highlight that followers' pursuit of self-branding, driven by self-consciousness, social consciousness, credibility, and social presence, significantly influences the impact of self-expressive products on the audience's purchase intention. The research contributes to micro-influence marketing theory by integrating mechanics, offering practical implications for micro-influencers, and suggesting future research agendas. The study also explores the characteristics of micro-influencers, their followers, and the mechanisms driving their impact on user behavior. It discusses the connections between changes in these attributes or mechanisms and subsequent economic conditions, brand marketing strategies, and follower psychology. The research identifies key journals and research focuses in the field, emphasizing the importance of interdisciplinary research. The study highlights the role of micro-influencers in shaping consumer behavior, particularly in the context of social media, and their impact on brand marketing and consumer perceptions. The research also examines the influence of micro-influencers during the pandemic, emphasizing their role in disseminating social awareness and health information. The study concludes that micro-influencers play a crucial role in shaping consumer behavior and brand marketing strategies, and future research should focus on further exploring the mechanisms underlying their influence.