Mental health problems contribute substantially to the disease burden in Sweden and worldwide. Such problems are not evenly distributed in the population and are, to a large extent, socially determined. The overall aim of the current thesis is to investigate the multigenerational associations and mechanisms between socioeconomic and psychosocial disadvantages and mental health problems, as well as potential gender differences. Drawing on data from the Stockholm Birth Cohort Multigenerational Study that encompasses local and national survey- and register-based data across three generations, and through employing structural equation modeling techniques, a series of four empirical studies was conducted. Study I demonstrated multigenerational transmission of low income through the patriline (from paternal grandfathers to fathers) to grandchildren, and multigenerational transmission of psychiatric disorders through both the patriline and matriline (from maternal grandmothers to mothers) to grandsons. The patriline-grandson transmission of psychiatric disorders partially operated via low income of the fathers. Additionally, grandparents’ psychiatric disorders influenced their children’s and grandchildren’s income. Study II provided further insights into multigenerational patterns of disadvantages by showing that combinations of grandparental socioeconomic and parental psychosocial disadvantages elevated the risks of grandchild psychiatric disorders. Importantly, improved socioeconomic and psychosocial circumstances across previous generations predicted lower probabilities of psychiatric disorders among grandchildren. Study III established the mediating role of psychosocial disadvantages in the parental generation, particularly among mothers, in the association between grandparental socioeconomic disadvantages and grandchild psychiatric disorders. Study IV delved deeper into the mechanisms underlying this multigenerational mediation pattern by identifying parental childhood experiences (i.e., family relationship quality, peer relationships, and educational performance) as important determinants of parental adulthood psychosocial disadvantages and grandchild psychiatric disorders. Parental childhood peer relationships and educational performance mattered more among fathers, whereas family relationship quality played a more important role among mothers. These empirical studies extend our understanding of the multigenerational transmission patterns of disadvantages, and how multiple factors in the parental generation act as mechanisms linking grandparental socioeconomic disadvantages to grandchild mental health problems. Accordingly, public health efforts to improve mental health of future generations could benefit from a multigenerational perspective.