Abstract: Objective To analyze influence factors related to insufficient lactation during mother-infant separation in neonatal intensive care unit(NICU).Methods Totally 260 newborn premature infants treated in ICU of Zhoukou Luyi Zhenyuan Hospital were recruited as study subjects from June 2018 to December 2020. They were divided into 2 groups based on the amount of lactation in 14 th day postpartum. The mothers who had inadequate lactation (＜ 500 m L/day) were in the observation group and who had adequate lactation (> 500 m L/day) were in the control group, with 130 cases in each group. Influence factors related to inadequate lactation were compared between 2 groups.Results There were significant differences as for maternal age, pregnancy complications, gestational weeks, postpartum breastfeeding initiation, Edinburgh Postnatal Depression Scale (EPDS) score, lactation phase II initiation time, daily sleep time, liquid intake, and milk sucking frequency between 2 groups(P＜ 0. 05). Logistic regression showed that maternal age, gestational weeks, complications during pregnancy, EPDS score, milk sucking frequency, lactation phase II initiation were risk factors related to insufficient lactation postpartum(P＜ 0. 05).Conclusion Factors leading to insufficient lactation during mother-infant separation should be focused. Clinically, the mother and newborn should be well evaluated in advance and factors affecting postpartum lactation should be effectively dealt with, so as to improve postpartum lactation and survival rate and living quality of preterm newborns in NICU.