AbstractLeader affective presence, the tendency of leaders to consistently evoke feelings in team members, has gained prominence in the context of leadership and teamwork. However, prior research lacks a comprehensive theoretical framework, focuses on limited team processes, and relies mainly on cross sectional designs to study this construct. Building upon theories of the social functions of affect, this study examines the relationship between leaders' affective presence and team member behaviour, specifically focusing on team proactive problem prevention and examining whether this relationship is mediated by team psychological safety. Using a two‐wave panel model with 504 professionals in 134 teams, our findings revealed that positive leader affective presence, characterized by instilling enthusiasm, joy and inspiration among team members, was positively associated with perceptions of team psychological safety. In turn, team psychological safety was positively related to leaders' assessments of proactive problem prevention. Interestingly, negative leader affective presence, which triggers worry, tension and stress, was not related to team psychological safety but was positively associated with team proactive problem prevention. These results highlight the importance of leader affective presence in shaping emergent team states and team member behaviour. Researchers and practitioners should thus consider these insights when assessing and intervening in leadership and teamwork processes in organizations.