We have developed a diagnostic method for pulmonary tuberculosis by detecting antibody to cord factor using enzyme-linked immunosorbent assay (ELISA). This study was to evaluate the usefulness of our method for a diagnosis of intestinal tuberculosis, and especially its ability to differentiate this disease from other inflammatory bowel diseases. Antibodies of the immunoglobulin G class against cord factor (trehalose-6,6'-dimycolate) from 27 patients with intestinal tuberculosis, 16 patients with Crohn's disease (CD), and 27 patients with ulcerative colitis (UC) were tested by ELISA with cord factor purified from Mycobacterium tuberculosis H37Rv as the antigen. Twenty-three of the 27 patients with intestinal tuberculosis (85%) showed elevated values distinct from healthy controls. None of the patients with CD showed an elevation of antibody titers. Of the 27 patients with UC, 26 (96%) did not show any anti-cord factor antibody elevation. We conclude that this method is simple and results are reproducible. The results of our study justify undertaking the detection of anti-cord factor antibodies to diagnose intestinal tuberculosis.