This article examines the parental potential of foster fathers and the factors that influence their involvement in childcare within foster families. The empirical basis of the study consists of focus group data collected from professionals working with foster families, as well as in-depth interviews conducted with foster mothers in St. Petersburg in 2024. The theoretical and methodological framework draws on the concept of parental potential, approaches to the professionalisation of foster parenting, social capital theory and studies of masculinity. The empirical analysis identified four types of fatherhood are (partner, functional, traditional, and passive), which differ in terms of their levels of involvement, patterns of interaction with the child and modes of role performance. The findings demonstrate that the parental potential of foster fathers is heterogeneous and is realised differently depending on the interplay of individual resources, family dynamics and institutional conditions. Particular attention is paid to the barriers to fathers' involvement, including gender norms, limited capacity for emotional reflection, the mediating role of mothers, and the mismatch between existing support formats and male modes of engagement. The study shows that the low and uneven participation of fathers in support practices is not only due to individual attitudes, but also to the institutional design of the support system. The results highlight the need to move from universal models of social support towards differentiated approaches that consider typological differences in fatherhood and the specifics of male engagement in parenting. This article makes a valuable contribution to the study of the gendered aspects of social policy and support practices for foster families.