Background: Longer exclusive breastfeeding duration has been associated with differences in neural development, better satiety responsiveness, and decreased risk for childhood obesity. Given its sensitivity to diet and contribution to regulating food intake through the integration of hormonal and cognitive signals, hippocampus may play a role in these relationships. Methods: We conducted a secondary analysis of 149, 7-11-year-olds (73 males) who participated in one of five studies that assessed neural responses to food cues. Hippocampal grey matter volume (GMV) was extracted from structural scans using CAT12, weight status was assessed using age- and sex-adjusted body mass index (%BMIp85), and parents reported exclusive breastfeeding duration and satiety responsiveness (Child Eating Behavior Questionnaire). Separate path models for left and right hippocampus tested: 1) the direct effect of exclusive breastfeeding on satiety responsiveness and its indirect effect through hippocampal GMV; 2) the direct effect of hippocampal GMV on %BMIp85 and its indirect effect through satiety responsiveness. %BMIp85 was adjusted for maternal education, yearly income, and prematurity while hippocampal GMV was adjusted for total intercranial volume, age, and study from which data were extracted. Results: Longer exclusive breastfeeding duration was associated with greater bilateral hippocampal GMV. While better satiety responsiveness and greater left hippocampal GMV were both associated with lower %BMIp85, hippocampal GMV was not associated with satiety responsiveness. Conclusions: While exclusive breastfeeding duration was not directly associated with weight status in children, these results highlight the potential impact of exclusive breastfeeding on hippocampal structure. Future studies need to determine the relative impact that complimentary feeding has on regional brain development and satiety responsiveness.