This study reviews the literature on the social and behavioral characteristics of only children in China. Of 16 studies that reported differences in the characteristics of only and non-only children, only 2 indicated that only children exhibited more socially desirable behaviors than did non-only children. The remaining studies reported that, compared with non-only children, only children were more spoiled, more selfish, less independent, and showed less emotional well-being. However, 13 studies found no differences between only and non-only children. These studies generally concluded that the number of misbehaving children is smaller than the number of well-behaved children regardless of sibling status; and the differences between only and non-only children are quantitative rather than qualitative, and less than the differences within the groups themselves. Further research must consider: (1) the effects of multiple factors, such as parents' formal certificate for having only one child, the one-child policy itself, and the availability of playmates; (2) children as active interactors with their environment; and (3) cultural differences between Chinese and Western children. Future research must correct the methodological shortcomings of existing studies. These shortcomings include an over-reliance on classroom observation and questionnaires, and poor test reliability. A list of 57 references is included. (BC)