OBJECTIVE： To study the effects of regular iron supplementation on hemoglobin and perinatal complication of pregnant women and neonates. METHODS： In retrospective analysis， the information of 606 pregnancy women were collected from Chongqing People’s Hospital during May 2016-May 2017. According to the regularity of iron supplementation， they were divided into regular iron supplementation group （142 cases）， irregular iron supplementation group （218 cases） and no iron supplementation group （246 cases）. The levels of hemoglobin in pregnant women were determined in 3 groups before childbirth and 3-7 d after childbirth. The incidence of gestational hypertension， premature rupture of membranes and puerperal infection in pregnant women were recorded in 3 groups.  Birth weights of neonates delivered by pregnant women were recorded in 3 groups， and the levels of hemoglobin in umbilical cord blood of neonates were also detected. Apgar score was used to evaluate whether neonates were born with hypoxia or asphyxia. The average days of hospitalization were counted for pregnant women of 3 groups. RESULTS： The levels of hemoglobin in regular ion supplementation group before and after childbirth were significantly higher than irregular ion supplementation group and no ion supplementation group； the incidence of gestational hypertension， premature rupture of membranes and puerperal infection were significantly lower than irregular ion supplementation group and no ion supplementation group， average hospitalization days were significantly less than irregular ion supplementation group and no ion supplementation group， the levels of hemoglobin in umbilical cord blood of neonates and birth weight in regular ion supplementation group were significantly higher than irregular ion supplementation group and no ion supplementation group， with statistical significance （P＜0.05）. There was no statistical significance in the incidence of constipation in pregnant women and the ratio of Apgar score of the neonates ＜7 among 3 groups （P＞0.05）. CONCLUSIONS： Regular iron supplementation can remarkably decrease the incidence of anemia， gestational hypertension， premature rupture of membrane and puerperal infection in pregnant women， shorten average hospitalization time， and increase average birth weight of neonates and the level of hemoglobin in umbilical cord blood.