The family is the environment that children are first exposed to after birth and is the environment that has the earliest and longest impact on children. Therefore, the family environment is of particular importance for children’s development. In terms of personality, those differences in the innate biological sense are further amplified with interactions with family members. The influence of the family on the child comes from a variety of sources, including the characteristics of the parents themselves, their parenting concepts and styles, parent-child attachment; the structure of the family, the arrangement of the environment, and so on. Based on studies by D. Baumrind and E. E. Maccoby, parenting styles can be classified into four types: authoritative, authoritarian, coddling, and indifferent, based on two dimensions: control (whether to make mature demands) and love (whether to care for the child). It is generally believed that authoritative parenting styles are most conducive to the development of good personality qualities in children. However, it has also been found that authoritarian parenting in Eastern cultures is sometimes more effective for children’s development. The nuclear family, extended family, and single-parent family are the three main family structures. The nuclear family refers to a family consisting of a couple and one child. As a unique social phenomenon, the psychological development of the only child has been the focus of psychologists’ attention. The general view, based on a large body of research in the field, is that only children have an advantage over non-only children in terms of cognitive development and academic achievement; in terms of personality, there are significant differences within only children, such as conformity, with only children enrolled in nursery and kindergarten being much stronger than children not enrolled in school, and that the differences between only and non-only children diminish or even disappear as they get older. Perhaps only children do not have developmental advantages or disadvantages per se, but their development depends mainly on some mediating factors in the family environment. Large families, i.e., families with several generations together. Such families have more time for adults to educate and caress their children, but are prone to intergenerational spoiling, as well as inconsistency in the concepts and methods of educating children, thus leaving them at a loss and forming undesirable personality traits such as anxiety and fear. A single-parent family is a family consisting of only one parent and the child. As traditional concepts of marriage and family are weakening and the divorce rate is increasing, single-parent families are becoming an increasingly common social phenomenon. Children in single-parent families are disadvantaged in many ways compared to children in intact families: children in single-parent families are more susceptible to deviant behavior and have more emotional and behavioral disorders due to pressure from friends. Children in father-absent families have more personality problems and are more likely to commit crimes.