The purposes of this study were to investigate the degree of self-differentiation and the relationship between the degree of self-differentiation and conflict-coping behaviors. The results were summarized as follows; 1. The degree of self-differentiation was medium level of both husbands and wives. The degree was significantly high for husbands compared with that for wives. 2. As for behaviors of conflict-coping, most surveyed couples answered reasonable countering while the use of physical power was their last method of coping conflicts. Wives resort to external help or reliance on religion more than husbands do. Exercises of physical power were used more by husbands than wives. 3. There were significant differences in the degree of self-differentiation and conflict-coping behaviors according to back ground variables. 4. There was significant relation between the degree of self-differentiation and conflict -coping behaviors, and that one of the spouses whose self-differentiation was relatively low uses more evasion and exercises of physical power.