In this study, we examined maternal reflective functioning as a bi-dimensional construct in a sample of 47 mothers with drug use disorders caring for infants and toddlers. We first tested a two-factor solution with scale items from the Parent Development Interview and confirmed the presence of two related but distinct dimensions: self-mentalization and child-mentalization. We then tested predictions that (a) self-mentalization would be associated with overall quality of maternal caregiving and that (b) child-mentalization would be associated with (i) maternal contingent behavior and (ii) child communication. Results partially supported hypotheses (a) and (bii). Unexpectedly, self-mentalization alone was associated with maternal contingent behavior. Findings suggest that self-mentalization may be a critical first step in improving mother-child relations involving mothers with drug use disorders. Implications for theory and practice are discussed.