The purpose of this study was to investigate the psychological trait of Japanese national synchronized swimmers at different levels of performance. We analyzed the scales of psychological competitive ability for synchronized swimmers of national A team (22.3 ± 2.2 yrs, n = 12), national B team (18.0 ± 2.2 yrs, n = 8), junior national team (15.8 ± 0.4 yrs, n = 8) and junior elite team (12.7 ± 0.7 yrs, n = 14), by using the Diagnostic Inventory Psychological Competitive Ability test (DIPCA.3.). Results revealed that synchronized swimmers were significantly high in cooperation, patience and volition for self-realization, and significantly low in their ability to relax, self-confidence and decision-making ability as compared to Olympic female athletes. It is suggested that the psychological competitive ability of synchronized swimmers were reflected by specific factors of synchronized swimming, which is judged as a closed-skill, synchronized sport and a large repetitive drill. Although world class synchronized swimmers had a low ability to relax, it is suggested they can perform better under high pressure and tension. The national A team was higher in patience and aggressiveness than the lower level groups. Therefore, patience and aggressiveness are important abilities that are required to be a world top-level athlete. In addition, younger swimmers need to gain experience by participating in international competitions and national team training camps at a young age in order to improve their psychological competitive ability.