The purpose of this series is to describe findings seen on abdominal sonography in neonates with erosion into the liver by umbilical vein catheters (UVCs). Four neonates with erosion of the UVC into hepatic parenchyma within a 2-year period were identified. A retrospective case analysis was performed to determine the symptoms and clinical scenario of presentation. Plain radiographs were examined to establish the location of the UVC placement, and abdominal sonograms were reviewed. All 4 neonates had abdominal distension within 9 days of UVC placement, and in all of them, the UVC tip was located below the hemidiaphragm and superimposed over the liver. Sonographic examination of all patients showed intraparenchymal liver lesions with an echogenic rim and hypoechoic center. Two neonates also had subcapsular fluid collections. Complex ascites was seen in all 4 patients. The fluid was proven to be total parenteral nutrition by paracentesis in 2 patients. Treatment consisted of removal of the UVC. All patients were followed for a period of 2 to 18 months and showed clinical resolution of symptoms or sonographic improvement of the liver lesions. A characteristic liver lesion can be seen on sonography with hepatic erosion by UVCs. Our study shows the importance of a high index of suspicion of UVC erosion into the liver in neonates with catheters positioned in the liver. When such neonates have abdominal distension, prompt abdominal sonograms should be obtained.