The purpose of this paper is to clarify the theoretical characteristics of the family groups, which is an encounter groups of the person-centered approach targeting families in the child-rearing period in Japan, and to present basic findings for understanding this from the overall perspective of clinical psychology. First, it was examined how the family groups, which targets families, can be theoretically positioned and understood as an encounter groups in the person-centered approach, which targets individuals. As a result, it was suggested that it is possible to understand the family groups from the viewpoint of object, purpose, structure, and facilitation. Next, the theoretical characteristics of family groups were examined by comparing them with multiple family group therapy and family camps, which also target multiple families and have different theoretical backgrounds. As a result, it was found that parents’ awareness of their own family relationships, which is caused by the relationships and comparisons among multiple family members in the family groups, is common in the other two approaches. Furthermore, it was shown that family camps with a high degree of structural similarity to family groups have in common the liberation from family roles and the contribution to relationships through the sharing of experiences within the family. Although these two approaches and family groups suggest similarities in the dynamics that occur in families, family groups are unique in that they have the facilitation of the person-centered approach.