Abstract Conversational artificial intelligence (CAI), as an emerging digital tool, holds distinct potential for enhancing adolescents health literacy and fostering proactive health behaviors. In light of the increasing need for upstream prevention and early intervention in adolescent physical and mental health, the review systematically synthesizes current evidence on the role of CAI in shaping proactive health behaviors. It dissects the underlying mechanisms of CAI through a triple logic framework: technological context driven, psychological motivation activation, and behavior generation and maintenance.It also maps the evolving applications of CAI in areas such as psychological support and lifestyle interventions. Finally, it outlines future prospects, emphasizing the strengthening of agency awareness cultivation and human-computer collaborative interventions, aiming to provide a theoretical foundation and practical guidance for leveraging CAI to power adolescents in developing proactive health behaviors.