This is an unusual case in comparison to other sonographically described prenatal cases due to very early diagnosis and surgical intervention following prompt delivery. A 40-year-old pregnant, ultrasonography showed presence of cystic structure in the fetal abdomen that was consistent with intestinal dilatation. At 32 weeks' of gestation, repeat ultrasound showed collapse of the bowel dilatation along with the presence of hyperechogenic fluid in the fetal abdominal cavity. Cesarean section was performed. The clinical utility of this report is the recognition that meconium peritonitis (MP) may be diagnosed in the acute phase with typical ultrasound features, and should be considered in the differential diagnoses of cases presented with reduced fetal movements. Although it appears that morbidity and mortality in MP cases depend upon gestational age, this case report may help to manage similar cases for defining the appropriate delivery time and treatment modality after prenatal identification of the problem.