Objective To analyze the application of nutritional dietary guidance in pregnant women and explore its effects on pregnancy complications and maternal-infant outcomes. Methods 110 cases of women with singleton pregnancy in department of obstetrics and gynecology of our hospital were selected and randomly divided into nutrition group and routine group, with 55 cases in each group. Routine group was given routine pregnancy guidance method, and nutrition group was given nutritional dietary guidance according to the condition of pregnant woman on the basis of routine group. The pregnancy complications during pregnancy (gestational hypertension, gestational diabetes mellitus, gestational anaemia) and maternal-infant outcomes (vaginal delivery, dystocia, postpartum hemorrhage, premature delivery, low birth weight infant, fetal macrosomia) were observed in the two groups. Results The incidence rates of gestational hypertension, gestational diabetes mellitus and gestational anaemia in nutrition group were significantly lower than those in routine group (P<0.05). The incidence rates of vaginal delivery, dystocia, postpartum hemorrhage, premature delivery, low birth weight infant and fetal macrosomia in nutrition group were better than those in routine group (P<0.05). Conclusion Nutritional dietary guidance in pregnant women can reduce pregnancy complications, increase the rate of natural delivery, and improve the birth quality of newborns.