Background: Parents' behaviors could contribute to the development of their children's weight-related health behaviors. Purpose: Relationships of young adults' (N = 151) and their parents' weight-related behaviors were examined along with parental authority styles. Methods: Questionnaires were completed by young adults and their parents. Comparisons of BMI, energy consumption, and energy expenditure were conducted with correlation analyses and paired-samples t-tests. Multiple regression analyses were used to further explore the influence of parental authority. Results: Parents' weight statuses and dietary behaviors were positively associated with those of their young adult children (P less than 0.001 for both). When controlling for gender, at high levels of authoritarian and permissive parental practices, young adults tended to have weight statuses that were inversely related to those of their parents (P less than 0.001 for both); at high levels of authoritarian parenting, young adults also tended to follow dietary consumption patterns that were inversely related to those of their parents (P less than 0.001). Physical activity behaviors of young adults and their parents were not related. Discussion: This study provides evidence that parental behaviors influence children's lasting weight-related health behaviors. Translation to Health Education Practice: Health educators and counselors who aim to influence weight-related health of children should consider the role of parents and of parental authority styles. (Contains 4 tables and 3 figures.)