Subjective well-being is an important content of positive psychology. The adolescent period is the key to individuals’ growth and development. Researches of adolescences’ subjective well-being can not only enrich the research of developmental psychology, but also can help them to get better sense of well-being as well as promote their development of mental health. According to the developmental conceptualism, individuals’ development is realized by the continuous social interactions between them and their situations. Family environment is the most important environment for children’s, adolescents’ and parents’ growth and development. As the main component of family environment, it plays a vital role in the growth of children and adolescence. Previous studies have shown that aggression, marital conflict, education achievements and so on have intergenerational transmission effects, while there are few studies on the intergenerational transmission effect of subjective happiness. Therefore, the first purpose of the current study was to test whether parents’ subjective happiness would affect their children’s subjective well-being. In the family, parent-child communication is an indispensable link, and a large part of the influence of parents on adolescence is through the function of verbal communication. Therefore, the second purpose of this study was to test whether the parent-child communication played an intermediary effect between parents’ subjective happiness and adolescents’ subjective happiness. Adolescent individuals pursue emotional independence and gradually establish emotional connections outside the family. Therefore, individuals with different emotional autonomy may have different levels of communication with their parents. Therefore, the third purpose of this study was to test whether adolescent emotional autonomy played a moderating effect. Taking the adolescences of middle school students and their parents in 292 families as the research objects, the intergenerational transmission effect of parents’ subjective well-being and adolescent subjective well-being was investigated by the questionnaire survey method, and the mediating effect of parent-child communication and the moderating effect of adolescent emotional autonomy were also discussed. The results show that: (1) parents’ subjective well-being could significantly predict the adolescent subjective well-being of middle school students. (2) Parent-child communication played a partial mediation in parents’ subjective well-being and adolescent subjective well-being of middle school students. (3) Adolescent emotional autonomy could regulate the influence of parent-child communication on adolescent subjective well-being in middle school students. Adolescences with low emotional autonomy were more likely to be affected by parent-child communication in their subjective well-being, while individuals with high emotional autonomy would reduce the role of parent-child communication. The results of this study not only enriched the previous studies on the factors of subjective well-being, but also added the intergenerational transmission theory in the field of psychology. It explained the mechanism of action of subjective well-being inter-generational transmission effect, and provided theoretical basis and guidance for the cultivation of parent-child relationship and the establishment of children’s positive emotion. However, there are some limitations in this study. For example, subjective reporting method is mainly adopted in the measurement of subjects, because there may be social desirability. In addition, this study takes adolescent subjective well-being as the dependent variable, and adopts the method of cross-sectional study. It is impossible to determine whether this relationship still exists over time.