Purpose: To evaluate the usefulness of ultrasonography for the diagnosis of gastrointestinal disease in a rural primary care setting. Subjects and Methods: Over a 24-month period, 267 consecutive patients were examined using transabdominal ultrasound (US), of whom 183 had clinical abdominal symptoms, 31 had abnormalities on blood test, and 53 had neither of them. Results: In 58 (32%) of 183 patients with abdominal symptoms, US detected gastrointestinal disorders (38 infectious enterocolitis, four gastric ulcer, four bowel obstruction, three ischemic colitis, three constipation, two appendicitis, one duodenal ulcer, one mesenteric lymphadenitis, one colonic diverticulitis, and one sigmoid colon cancer). The sensitivity and specificity of US were 85% and 86%, respectively. US often yielded important information about the urgency of diseases and let us know the necessity of referral. Conclusion: Ultrasonography plays an important role in establishing a correct diagnosis of gastrointestinal disease in primary care.