One of the reasons why contingency theory of organizational structure has not been particularly successful is its failure to consider more important contingency variables related to organizational structure. Among the new variables thought to be related to organizational structure are the psychological characteristics of organizational members. While considerable research has been conducted on the relationship between top managers' psychological characteristics and organizational structure, the psychological characteristics of employees and other organizational members have been excluded from investigation. This study establishes a model and hypotheses regarding the relationship between organizational structure and performance by considering the psychological characteristics of both top managers and organizational members, and tests them using data from Korean firms. The results reveal that the psychological characteristics of organizational members are indeed related to organizational structure and firm performance.