ABSTRACTBrand evangelism has become an increasingly relevant concept in consumer–brand relationship research, yet existing studies remain fragmented, lacking a structured synthesis of its antecedents, mechanisms, and outcomes. This study conducts a systematic literature review (SLR) to consolidate current knowledge on brand evangelism, identify key thematic clusters, and highlight research gaps. Using the Antecedents, Decisions, and Outcomes and Theories, Contexts, and Methods frameworks, aligned with the Scientific Procedures and Rationales for Systematic Literature Reviews protocol, this review provides a comprehensive understanding of brand evangelism. A bibliometric analysis of 41 articles, supported by thematic mapping, reveals four primary research clusters: brand‐centric relational evangelism, green evangelism, social media evangelism, and emotional evangelism. The findings contribute to both theory and practice by offering a structured research agenda and strategic insights for fostering brand evangelism. This study serves as a foundational resource for scholars and practitioners, guiding future research, and managerial applications in brand evangelism.