Introduction: Biomass (organic) fuels cause indoor air pollution when used inside dwellings. We evaluated the frequencies of chronic obstructive pulmonary disease (COPD) and chronic bronchitis (CB) among rural women using biomass fuels for heating and cooking and compared them to women living in urban areas where such fuels are not used. Methods: From electoral lists we randomly selected 242 women living in rural areas near Kayseri, Turkey and 102 women living in apartments in the city having central heating and cooking with fuels other than biomass ones. Using a translated version of the American Thoracic Society questionnaire, with additional questions from the British Medical Research Council questionnaire, trained interviewers conducted personal interviews. They also collected information on fuels used for cooking and heating. All study subjects underwent a physical examination and measurement of pulmonary function. Results: We found that rural women were younger than urban women (mean age [and standard deviation], 40.5 [14.1] yr v. 43.6 [11.9] yr). More urban than rural women were current (14.7% v. 4.5%, p < 0.001) or past (11.8% v. 1.2%, p < 0.001) smokers. CB was more prevalent among rural women than urban women (20.7% v. 10.8%, p < 0.03). Similarly, COPD was more prevalent in rural women (12.4% v. 3.9%, p < 0.05). Although the pulmonary function tests were within normal limits, FEV1 values in rural women were found to be relatively low compared with those of urban women (p < 0.05). Interpretation: Rural women exposed to biomass fumes are more likely to suffer from CB and COPD than urban women even though the prevalence of smoking is higher among the latter group.