The purpose of the present study is to understand the change in the relation between mother-in-law and daughter-in-law according to the social change in comparison with the survey effects in 1974 (ko Jung-Ja) and 1985 to find out the cause of conflict in both side of power structure and affection structure, indicating behavior, the influences on the relationships among family, possible meditators. this thesis was made by an experimental research. Data were collected from 146 mothers-in-law and 141 daughters-in-law in Pusan. The collected data were analysed by statistical methods such is as follows, 1. cause of conflict In power structure the cause of conflict is, in the case of mother-in-law opinion opposion and shaughty attitude by daughter in-low and, in the case of daughter-in-law, domestic dominance. It is thought that there is a difference of viwew between mother-in-law and daughter-in-law about the possesion of economic dominance and many conflicts rises because of economic dominance. but the study in 1985 than 1974 suggests the possibility of conflict meditator because mother-in-law and daughter-in-law do homework dependently in the practice of power. In affection structure, the chief dissatisfaction toward daughter-in-law showes the change in time. In 1974, there was no affection and respect. In 1985, the rate of doing without consultation was high. Also, the lack of communication of mother-in-law and daughter-in-law is the cause of conflict. 2. Indicating behavior the rate of thinking alone if high in both sides. But in the survey of 1985, the covert verbal aggressive action with which mother-in-law appeals to her daughter and daughter-in-law to husband is rising. 3. Influence on the relationship among family by the conflict between mother-in-law and daughter-in-law. the conflict between mother-in-law and daughter-in-law play negative effects on the intimacy and relation between husband and wife. 4. Conflict mediation behavior As compremiser, it is suggested that in the case of daughter-in-law the position and role of husband is important and, in the case of mother-in-law respects mother-in-law, daughter-in-law and gives her the role.