A 3-yr-old intact male dingo (Canis familiaris dingo) presented with a 3-mo history of diarrhea. The diarrhea did not resolve with antibiotics or intestinal protectants. Fecal examination for parasites, fecal cultures, physical examination, and radiographs were unremarkable. Enteroscopic duodenal biopsies showed dilated lacteals without inflammation. Results of serum folate, cobalamin, and trypsin-like immunoreactivity were normal. Low serum total protein and albumin combined with increased fecal levels of alpha-1 protease inhibitor suggested the diagnosis of lymphangiectasia. Full-thickness intestinal biopsies of the duodenum, jejunum, and ileum revealed dilated mucosal and submucosal lacteals without associated inflammation, confirming the diagnosis of primary lymphangiectasia. Currently, the dingo is being maintained with nutritional management.