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Neonatal ascites is a condition characterized by abdominal distention resulting from the accumulation of fluid within the peritoneal cavity and is life-threatening if not treated appropriately. Genitourinary abnormalities and urinary ascites are important to consider as part of the differential for newborns presenting with abdominal distention and ascites. In male infants with urinary ascites, presence of a posterior ureteral valve is a common etiology, accounting for up to 70% of cases. In this setting, early identification and management of urinary outlet obstruction is essential to prevent progression to autodialysis and uremia. Here we present a case of late preterm male with abdominal distention and imaging consistent with urinary ascites due to presence of bilateral posterior ureteral valves successfully treated by laser ablation.