Objective To explore the effect of the nursing intervention for Internet+whole course breastfeeding support based on lactation physiology on exclusive breastfeeding of cesarean section women.Methods Using the convenience sampling method,198 women who were from prenatal examination to delivery in the Obstetrical Department of a tertiary hospital in Nanning city from July 2022 to February 2023 were selected,with 99 women in each group.The experimental group adopted the nursing intervention for Internet+whole course breastfeeding support based on lactation physiology,while the control group adopted routine nursing care.The rates of exclusive breastfeeding within 6 months,breastfeeding or milking frequency within 3 days postpartum,incidence of nipple pain,breastfeeding knowledge scores,and breastfeeding self-efficacy scores were compared between the 2 groups.Results No shedding occurred in both groups.The exclusive breastfeeding rates in the experimental group at postpartum 3 days,14 days,42 days,4 months,and 6 months were higher than that in the control group.The comparison of the rates of exclusive breastfeeding between 2 groups at different time points showed that the intergroup effect,time effect and interaction effect were statistically significant(P＜0.05).The 2 groups were stratified by maternal and child separation,and the rates of exclusive breastfeeding of the experimental group at postpartum 42 days,4 months and 6 months were higher than that of the control group(P＜0.05).The frequency of breastfeeding or milking within 3 days postpartum,incidence of nipple pain,breastfeeding knowledge scores,and breastfeeding self-efficacy scores were higher in the experimental group than those in the control group(P＜0.05).Conclusion The nursing intervention for Internet+whole course breastfeeding support based on lactation physiology can improve the compliance of lactation behavior in cesarean section women and promote the establishment of lactation,which can significantly improve the rate of exclusive breastfeeding within 6 months.