Occupational asthma is one of the category of work-related asthma. The diagnosis of occupational asthma is established on the basis of a suggestive history of a temporal association between exposure and the onset of symptoms and objective test that these symptoms are caused by specific agent at work. Besides pharmacological treatment management of OA include removal from exposure or reduction of exposure through workplace control measures. Prevention of new cases is the best approach to reducing the burden of asthma attributable to occupational exposures.