Tannery workers are exposed to many chemical and physical hazards. The current study involved 730 workers from 23 leather factories located in the Tuzla Organized Industry Region, Istanbul. Participants were interviewed and underwent clinical examination. After the basic physical examination, respiratory functions were measured by spirometer and the workers questioned about asthma. Health problems included gastrointestinal complaints (730%), bronchitis (3.11%) and asthma (3.0%). Signs of bronchial obstruction - wheeze and rhonchus - were detected in 71 (9.72%) workers. A deficit in the values of FVC%, FEV1%, FEV1/FVC%, PEF%, FEF25-75% was set nominally at 80% of the respiratory function test parameters. Decreased pulmonary function results were found for FVC% in 36 (4.93%) workers, FEV1 in 71 (9.72%), FEV1/FVC in 18 (2.59%), PEF in 183 (25.1%) and FEF25-75% in 204 (2794%). The number of those with respiratory obstruction detected by spirometry was 294 cases (40.27%), more than the number of cases, 263 (36.02%), who claimed respiratory problems in the questionnaire. This study was a contribution towards efforts to improve the factory environment and control workplace risks. Together with medical examinations before and during employment and provision of continuous health services and training will reduce the risk of occupational disease to a minimum.