Neonatal ascites is an uncommon problem that may be caused by a number of etiologies including diseases of genitourinary system and gastrointestinal system, cardiac disease, hepatic disease, systemic infection such as TORCH or parvovirus, chylous, ovarian cause, inborn error of metabolism and idiopathic. We reported two cases of neonatal ascites, one was caused by cytomegalovirus and no obvious causes could be detected in the second one. The ascites were diagnosed by prenatal ultrasound at the gestational age of 25 weeks and 37 weeks respectively and were resolved spontaneously after birth. One-year follow-up of both cases revealed normal growth and development. No recurrent ascites could be detected by abdominal sonography except for evidence of mild hepatomegaly that was noted in case 1. Thus, isolated fetal and neonatal ascites without other concomitant abnormalities were diagnosed, a separate entity from non-immune hydrops fetalis with excellent prognosis.