Significance Mitochondrial physiology affected by childhood maltreatment (CM) might be a biological link for the intergenerational transmission of CM-related consequences. As mitochondria are intergenerationally transmitted from mother to child, alterations in mitochondrial bioenergetics might influence how maternal CM affects physical and mental development as well as functioning in their children. Our study reports data on mitochondrial bioenergetics in peripheral mononuclear immune cells of mother-newborn dyads, which were positively correlated. Higher maternal maltreatment load was associated with higher mitochondrial respiration and density in mothers, but not in their newborns. Thus, we found no evidence for an intergenerational effect of maternal CM on mitochondrial bioenergetics in immune cells of their newborns.