Objective To explore the value of MRI in diagnosis of fetal meconium peritonitis.Methods Seven meconium peritonitis fetuses proved by surgery and pathology were enrolled.The prenatal MRI findings and clinical data were analyzed retrospectively.Results Six fetuses showed a large amount of ascites,intestinal tube floating in the abdomen,small intestine gathered together.One fetus showed a giant abdominal cystic mass,with bowel compressed,displaced and uneven dilated.Four fetuses showed small colon and rectum,or without meconium signal.Two fetuses were accompanied by bilateral hydrocele.Amniotic fluid increased in 3 cases.After the neonates were born,1 case of them died from sudden heart rate decline during operation,1 case died from severe pulmonary edema after operation,and 5 cases survived after operation.Conclusion MRI has some features in the prenatal diagnosis of meconium peritonitis,which can provide an important basis for postpartum treatment and evaluation of prognosis.