The aim of the present study was to examine the efficacy of low fat diet against dyspepsia associated with non-alcoholic mild pancreatic disease. Patients with upper abdominal pain suggesting pancreatic disease (persistent over hours, pain aggravated by ingestion of food, epigastric pain radiating to the back), without a history of alcohol consumption and who exhibited no abnormalities regarding serum amylase and lipase, ultrasonography, CT and upper gastrointestinal endoscopy, performed a low fat diet (less than 20 g of fat / day) for 4 weeks. The patients were subjected to endoscopic ultrasonography (EUS) before the diet therapy and were distributed into those who had 5 or more minor features of chronic pancreatitis (suggestive group), 3 or 4 (indeterminate group) and those with 2 or less (control group) based on the Rosemont criteria for the diagnosis of chronic pancreatitis. Patients with major features were excluded. Symptom severity was recorded before and after the diet therapy using a 10-cm visual analog scale (VAS). Among 45 patients, 12 were in the suggestive group, 19 were in the indeterminate group and 14 served as controls. A significant improvement of symptoms was observed only in the suggestive group. Low fat diet may serve as a therapeutic effect for patients with dyspepsia associated with non-alcoholic mild pancreatic disease based on EUS.