Breast milk is considered the gold standard for infant nutrition, but many factors can hinder milk production. Mothers of infants in the Neonatal Intensive Care Unit (NICU) are especially prone to stress, which can inhibit volume of breast milk. The purpose of this study was to determine if music listening had an effect on the volume of breast milk pumped and relaxation level of mothers of infants in a NICU. A total of 28 participants, who were mothers of infants in the NICU, were included in the data analysis of this study, with 14 in the control group and 14 in the experimental group. Participants assigned to the experimental group listened to relaxing music during pumping sessions in the NICU, for the duration of their infant’s stay. Participants assigned to the control group pumped as they would normally without the music condition. Results indicated that there was a significant increase in relaxation scores in the music group, but no significant difference in volume of milk pumped. Further research should be done in this area to determine music’s effect on volume of milk pumped by mothers of infants in the NICU.