This study examines convergent and discriminant validity of the 360 degree feedback systems in which managerial behavior and performance are evaluated by multiple raters including bosses, peers, subordinates, and self. Multitraitmultirater (MTMR) correlation matrix was constructed from the data of 177 Japanese managers and 1, 187 coworkers. The matrix was investigated by zero-order correlations and confirmatory factor analyses (CFA). Results of correlation analyses found that 1) in any domain of managerial behavior (traits), ratings within the same rater were correlated highly, proving that discriminant validity was low; and that 2) ratings of the same trait provided by different raters were not associated highly, suggesting that convergent validity is questioned. Confirmatory factor analyses found that among three models, i.e., rater model, trait model, and rater-trait combined model, the combined model fit best, suggesting that both rater effect and trait effect were interwoven in the actual ratings of the 360 degree feedback.