Objective: This study investigated the validity of the Social Emotional Health Survey--Primary (SEHS-P;Furlong et al., 2013), which assesses four wellness dispositions (gratitude, optimism, zest, and persistence) associated with positive youth development. Method: The sample included 995 Japanese elementary school students (Grades 4-6) attending one of four schools in and nearby Tokyo. A confirmatory factor analysis tested the fit of the hypothesized SEHS-P factor structure. Results: The model adequately fit the data. As hypothesized, items showed good factor loadings on the corresponding four factors. All parameter estimates were statistically significant (p < 0.01). Criterion validation examined associations between the SEHS-P and measures of psychological distress and satisfaction with classroom life. Validation coefficients were moderate to large size (0.37 to 0.57). Reliability was good for each subscale (Alpha and Omega coefficients = 0.83 to 0.97). Conclusion: This preliminary validation of the Japanese version of SEHS-P provides a step towards introducing a much-needed, whole-school universal screening approach to support positive education in Japanese schools.