Organ(1988) has suggested that OCB should be considered an important component of job performance because citizenship behaviors are part of the spontaneous and innovative behaviors. Also it has been suggested that organizational characteristics may potentially explain many organizational behavior outcome variables(Hackman & Oldham, 1980). In recent years there has been a resurgence of interest in the validity of personality measures as a moderator between many variables and organizational outcome variables. This is largely due to the facts that first personality is difficult to control for promoting many organizational outcomes and next many researchers have found the moderating effects of personality(Brief & Aldag, 1975; Wanous, 1974). The purpose of this research is to test the moderating effects of tenure and growth needs on the relationships between organizational characteristics and OCB. To assess the moderating effects, the hierarchical regression procedures outlined by Cohen and Cohen(1983) were followed. On the basis of data from 698 teachers in Wonju province, results indicated that job variety has more impacts than any other independent variable on OCB like other studies. It is found that job variety and job identity have more impacts on courtesy and altruism in lower growth needs group than in higher growth needs group. Also it is resulted that job importance and autonomy have more impacts on sportsmanship in higher growth needs group than in lower growth needs group.