The objective of the study was to determine the prevalence of smear-positive tuberculosis (TB) in a rural area in Bangladesh at Matlab. A TB surveillance system was established among 106,000 people in rural Bangladesh at Matlab. Trained field workers interviewed all persons aged > or = 15 years to detect suspected cases of TB (cough > 21 days) and sputum specimens of suspected cases were examined for acid-fast bacilli (AFB). Of 59,395 persons interviewed, 4235 (7.1%) had a cough for > 21 days. Sputum specimens were examined for AFB from 3834 persons, 52 (1.4%) of them were positive for AFB. The prevalence of chronic cough and sputum positivity were significantly higher among males compared to females (P < 0.001). The population-based prevalence rate of smear-positive TB cases was 95/100,000 among persons aged > or = 15 years. Cases of TB clustered geographically (relative risk 5.53, 95% CI 3.19-9.59). The high burden of TB among rural population warrants appropriate measures to control TB in Bangladesh. The higher prevalence of persistent cough and AFB-positive sputum among males need further exploration. Factors responsible for higher prevalence of TB in clusters should be investigated.