Pathological sections of gastrectomized specimens of 74 patients with benign gastric ulcer and 79 with gastric cancer were reviewed. Intestinal metaplasia was found in 26 specimens with benign ulcer (35.1%) and in 43 with cancer (54.4%), a difference that is statistically significant. Further analysis of age groups showed that rate of occurrence of metaplasia in cancer patients older than 60 years was 70.3%, which was significantly higher than that of their younger counterparts (40.5%) and of patients with benign ulcer of either age group. A survey was also conducted by taking biopsies of mucosa of antrum and body of the stomach of 250 patients who underwent gastroscopic examinations. Acute and chronic gastritis was found in 22 and 156 patients, respectively. Intestinal metaplasia was found to be associated with acute gastritis in 2 (9.1%) and with chronic gastritis in 25 (16%) patients. In conclusion, intestinal metaplasia was associated with higher proportion than it was with benign gastric ulcer and gastritis among Thai patients.