Background and Aim: Large airway obstruction is well described as a cause of apparent asthma, unresponsive to the standard asthma therapy. Our purpose is to introduce multiple variant of other diseases that mimic asthma with failure to treatment. Materials and Methods: Between 2005-2008, we evaluated clinical data of 10 patients presented with refractory asthma among a total of 3200 subjects referred to the interventional bronchoscopy and laser ward of Massih Daneshvari hospital. Results: The study population included 2 males and 8 females with a mean age of 42.1±18.9 years. Dyspnea was presented in 90% of patients. Chest X ray was normal in all, however, only 30% had normal chest CT scan. Endobronchial lesion was found in 80%, among which 75% were benign. Vocal cord dysfunction (VCD) was found in 10%, while 10% had external pressure on tracheal lumen. Patients were on asthma treatment for a mean of 24.4 months (a range, 5 to72 months). Conclusion: Asthma masqueraders, including several conditions that may confound a correct diagnosis of asthma. A careful clinical examination, high index of suspicion, and appropriate analysis of spirometry is essential for the appropriate diagnosis and management of asthma. If there was no progress in treatment after diagnosis further evaluation should be performed.