Abstract: By using 544 questionnaire samples, the mechanism of psychological ownership that has impact on organizational citizenship behavior is analyzed. Special attention is paid to the mediating effect of organizational identification and the moderating effect of the Chinese traditionality. Results indicate that: 1) the psychological ownership has a significant impact on organizational citizenship behavior (the correlation coefficient is 0421, P＜0000); and 2) organizational identification fully mediates the relationship between them, or it is through organizational identification that the psychological ownership affects the organizational citizenship behavior. By using moderated multiple regression, it shows that the Chinese traditionality moderates the relationships between the organizational identification and organizational citizenship behavior. In other words, for the staffs with lower traditionality, the relationship is positive, while for the staffs with higher traditionality, they are not significant related.