This research clarified the concrete contents of positive thinking and explored how positive thinking differs according to individual characteristics. Levels of trait anxiety and concerns about evaluation from others and the coaching environment, were defined as individual characteristics. The State-Trait Anxiety Inventory (STAI) for measuring trait anxiety was administered to a university male baseball team. Subsequently, one baseball player with high trait anxiety and one baseball player with low trait anxiety were interviewed. Semi-structured interviews focused on their thoughts during their baseball games and their individual characteristics. Interview data were transcribed verbatim and analyzed qualitatively. Positive thinking was classified according to eight patterns associated with the objects of attention, on 3 axes (emotional expression, body consciousness, and external concern), and the relationship between individual characteristics and positive thinking was considered. Greater trait anxiety and concern about evaluation from others seemed to indicate that self-control thinking contributed to performance. In contrast, when trait anxiety and concern about evaluation from others was lower, self-encouragement thinking was more likely to contribute to performance.