Objective To investigate the causes of chronic cough in Chongqing City and assess the efficacy of specific therapy. Methods A total of 233 consecutively non-selected referred patients ( 136 females) whose cough duration more than eight weeks were studied. Their age[ median ( range) ] was 44. 5( 15-78) yrs and cough duration was 2. 6 ( 0. 2-30) yrs. They were diagnosed using a diagnostic protocol based on the Guideline on Diagnosis and Treatment of Chronic Cough established by China Medical Association and American College of Chest Physicians. The etiological diagnosis was made according to clinical manifestations, lab examinations, and response to specific therapy. The effects was assessed four weeks after the drug withdraw. Results The cause of chronic cough was confirmed in 216 patients ( 92. 7% ) . Seventeen patients( 7. 3% ) had not been definitely diagnosed. Cough due to a single cause was found in 163 patients ( 75. 45% ) , and due to multiple causes in 53 patients ( 24. 53% ) . The causes included upper airway cough syndrome ( UACS) in 127 patients( 44. 4% ) , cough variant asthma ( CVA) in 73 patients( 25. 5% ) , gastro-esophageal reflux cough ( GERC) in 26 patients( 9. 1%) , postinfectious cough and angiotensin converting enzyme ( ACE) inhibitor-induced cough in 6 patients( 2. 1% ) , atopic cough in 5 patients( 1. 7% ) , chronic bronchitis in 3 patients ( 1. 0% ) , respectively. After specific therapy based on diagnosis, cough cured in 59 patients ( 25. 3% ) , and alleviated in 114 patients ( 49. 3% ) , no response in 40 patients( 17. 1% ) . Conclusion The causes of chronic cough in different areas maybe variant. UACS, CVA and GREC are the main causes of chronic cough in Chongqing City. Specific therapy is effective in majority of patients with chronic cough.