This cross-sectional study explored the relationships between dispositional flow, motivational climate, and self-talk in physical education. Six hundred forty-eight participants completed the Dispositional Flow Scale for Physical Education, the Learning and Performance Orientation in Physical Education Classes Questionnaire, and the Automatic Self-Talk Questionnaire for Physical Education. The results revealed that dispositional flow subscales were negatively related to students' negative self-talk dimensions and positively related to students' positive self-talk dimensions. Moreover, significant relationships emerged between perceived motivational climate subscales and students' self-talk dimensions. Hierarchical regression analyses showed that the dispositional flow subscale of unambiguous feedback and the subscale of motivational climate of students' learning orientation significantly predicted students' positive self-talk dimensions (positively) and negative self-talk dimensions (negatively). In contrast, the motivational climate subscales of students' worry about mistakes significantly and positively predicted students' negative self-talk dimensions. Finally, significant differences were found in study variables as a function of gender, leisure-time sport participation, sport type, and grade level. Overall, these correlational findings stress the importance of dispositional flow and perceived motivational climate in physical education as potential factors that shape students' self-talk.