Primary intestinal lymphangiectasia is a rare cause of protein-losing enteropathy and usually presents with intermittent diarrhea or malnutrition. Diagnosis depends largely on its pathologic condition demonstrating greatly dilated lymphatics mainly in the lamina propria of the mucosa. We report a case of primary intestinal lymphangiectasia, of the diffuse type, presenting with abdominal pain and voluminous diarrhea in a previously healthy 8-year-old boy. He had periumbilical pain for 3 months before presentation. He was managed by segmental bowel resections and end-to-end anastomoses. The histopathologic condition of the resected small intestine showed lymphatic dilation limited mainly to the subserosa and mesentery but was not prominent in the mucosa. Abdominal pain and diarrhea subsided postoperatively. The present case is the fourth report describing a response to operative resection.