Background: The aim of this study was to examine the internal consistency, structural validity, and convergent/known-group validity of the Japanese version of the 42-item Psychological Well-Being Scale (PWBS-42). Methods: The PWBS-42 includes six 7-item subscales designed to measure the following dimensions of eudaimonic psychological well-being: 1) autonomy, 2) environmental mastery, 3) personal growth, 4) positive relations with others, 5) purpose in life, and 6) self-acceptance. A questionnaire was administered to 2102 community residents in Tokyo aged 30 or over as a part of the Midlife in Japan (MIDJA) survey, in 2008. The internal consistency reliability was tested using Cronbach's α. Structural validity was examined using exploratory factor analysis (EFA). Convergent validity was evaluated by calculating correlations of the Japanese PWBS-42 subscales with life satisfaction, negative affect, negative adjectives, positive affect, positive adjectives, self-esteem, and perceived stress scales. Results: Data from 1027 respondents (505 males and 522 females) were analyzed (valid response rate = 56.2%). Cronbach's α values ranged from 0.70 to 0.78 for five of the subscales, while that for purpose in life was lower (0.57). EFA yielded a five-factor structure: The first two factors consisted of negative and positive items mostly from the environmental mastery, purpose in life, and self-acceptance subscales. The third, fourth, and fifth factors consisted mostly of items from the positive relations with others, autonomy, and personal growth subscales, respectively. As hypothesized, the scores for life satisfaction, negative and positive affect/adjectives, self-esteem and perceived stress were significantly correlated with all subscales of the Japanese PWBS-42. Conclusion: The subscales of the Japanese version of the PWBS-42 showed accep. levels of reliability and support for convergent validity in the Japanese population. The factor structure was slightly different from the theoretical 6-factor model: items of three subscales (environmental mastery, purpose in life, and self-acceptance) loaded together on two factors. This finding may be interpreted in light of the interdependent self construal found in Japan in which these three components could be closely linked.