A 7-month-old girl with history of persistent left chylous pleural effusion was referred for lymphoscintigraphy. A previous chest computed tomography (CT) scan demonstrated a small to moderate-sized left pleural effusion but could not identify the lymphatic leakage site. Lymphoscintigraphy using filtered Tc-99m sulfur colloid showed minimal focal activity in the lower chest. A correlative single-photon emission computed tomography (SPECT)/CT localized this activity to distal paraesophageal region, being highly suggestive of the site of lymphatic leakage. Subsequent lymphangiography confirmed these findings, revealing an abnormal lymphatic branch at the level of T10 and T11 vertebrae with retrocrural extravasation toward the left hemithorax. Thoracic duct embolization was accomplished at and proximal to the site of chyle leak using a platinum coil and n-Butyl cyanoacrylate glue. The patient was followed up for >24 months and demonstrated no recurrence of pleural effusion. No ascites or other complications related to the procedure were noted. The case demonstrates that Tc-99m sulfur colloid lymphoscintigraphy SPECT/CT can be a useful modality for detecting the chyle leakage site in children with chylothorax even when the amount of leakage is minimal.