Dispositional approach, a viewpoint which accounts for employees' behavior in the organization by their own personality, is one of the recent trends in Industrial and Organizational Psychology. In the present study, we focused on the Temperament and Character Inventory (TCI) as a significant scale of measuring disposition and yielded its test characteristics, utilizing Item Response Theory (IRT). Using 395 respondents, questionnaire survey was conducted which included TCI and Anticipatory Organizational Socialization Scale (AOSS). Results showed that there was unique correlation among the sub-scales of TCI and AOSS and that test characteristics of TCI sub-scales gained by IRT analyses were valid but needed further item analysis. Implications for applying TCI to newcomers selection and personnel assessment and future directions were discussed.