The purpose of this study was to investigate the effects of prenatal Qi exercise on mother–infant interaction and the behavioral state of the infant. A prospective, quasi-experimental design was used in 70 healthy pregnant women of more than 18 weeks of gestation. Pregnant women in the intervention group received 90 minutes of prenatal Qi exercise twice a week for 12 weeks. Prenatal Qi exercise group’s Nursing Child Assessment of Feeding Scale scores was higher in mother’s sensitivity to cues, responses to distress, socioemotional growth fostering, and cognitive fostering and for children in responsiveness. There was no significant difference in Anderson Behavioral State Scoring System scores between groups. The results suggested that prenatal Qi exercise is a valuable approach to positively influence mother–infant interaction postdelivery.