Family‐of‐origin systems are consequential for the emotional well‐being of offspring. These influences are likely to last into adulthood, affecting adult children's romantic relationships. The mechanisms by which family‐of‐origin environments influence adult romantic relationships are not fully understood. In a sample of 118 different‐sex couples, we tested the effects of negative family‐of‐origin conflict on adult offspring's provision of relationship maintenance to their romantic partner using structural equation modeling. We evaluated emotional dysregulation as a mediator of this effect, using two measures of emotional dysregulation. Results from structural models demonstrated a negative effect of family‐of‐origin conflict on the provision of relationship maintenance via higher levels of emotional dysregulation. Our results highlight emotional self‐regulation as a valuable intervention point for couple therapists.