The aim of this study was to explore the relationship of minority stress with experiences of parenthood (e.g. parental stress and parental justification) and child adjustment in lesbian mother families. Three components of minority stress were examined, namely, experiences of rejection as a result of the non‐traditional family situation, perceived stigma, and internalized homophobia. A total of 100 planned lesbian families (100 biological mothers and 100 social mothers) were involved in this study. Data were collected by means of a written questionnaire. The lesbian mothers in this sample generally described low levels of rejection, they perceived little stigmatization, and they also manifested low levels of internalized homophobia. However, minority stress was significantly related to experiences of parenthood. Lesbian mothers with more experiences of rejection experienced more parental stress, and appeared to defend their position as mother more strongly (e.g. parental justification). Furthermore, mothers with higher levels of perceived stigma and internalized homophobia felt significantly more often that they had to defend their position as mother. Finally, mothers who reported more experience of rejection were also more likely to report behaviour problems in their children. Our findings emphasize the importance of the effect of minority stress on the lives of lesbian mothers and their children.