Abstract: Family bereft of their only-child is a vulnerable group with intense media attention. Through field investigation in A and B two provinces, the differences in social support for two kinds of families bereft of their only-child were spotted:the ones that joined the self-organizations of families bereft of their only-child and the ones that are not members of such self-organizations. The former gets more formal social support and less informal social support, while the latter was given less formal social support, but the informal social support influences them relatively more obviously. In addition, the former holds high and "ideal-typed" expectations of social support with poor realizability, while the latter has low expectations, and most is a kind of "bottom line" expectations. Admittedly, the causes of the formation of differences are numerous, but there is no doubt that the self-organization plays an important role in it by influencing the attribution of death of the only-child, stimulated habits, rights consciousness, the identity to take responsibility, countervailing power and its "involution" which is hard to avoid. This has implications for carrying out differentiated and classified social support services, recognizing the duality of the self-organization and guiding its scientific development.

Key words: families bereft of their only-child, the self-organization of families bereft of their only-child, social support