In the current study it was investigated whether a maternal depressive disorder influences the mother-infant-interaction in infancy and the later ToM-understanding. Therefore, it was examined if there is a relationship between early mother-infant-interaction and later ToM-understanding. To our knowledge this is the first study that investigated gender as moderator for this relationship and that investigated if the infant’s ability of self-regulation is a predictor for ToM-understanding. It was examined if boys and girls of depressed mothers differ concerning their ability of (...) self-regulation. 53 mother-child dyads were studied over the period of 4 years, 20 mothers had a postpartum or lifetime depression, 33 mothers didn’t have any mental disorder. The mother-child-interaction was studied using the Face-to-Face-Still-Face-Paradigm. In preschool age ToM understanding was measured by using content-false-belief- and location-false-belief tasks. There was no difference between the mother-infant-interaction and ToM understanding between the experimental group and the control group. Furthermore, neither a relationship between early mother-infant-interaction and later ToM understanding nor a moderating influence of gender were found. Only the behavior of self-regulation during an interactive stress situation in FFSF was a marginal significant predictor for later ToM understanding for all participants. Furthermore, a significant difference between boys and girls was found within the experimental group. Girls of depressive mothers showed more behavior of self-regulation during an interactive stress situation than boys. Further research about the relationship between self-regulation in infancy and ToM understanding is needed. (shrink)