Immunity is responsible for the defense mechanism of the body but in case of autoimmunediseases, its role gets diverted. Like so many other diseases, asthma is also considered as one ofthe most common autoimmune diseases to be occurring in community. Asthma is defined as achronic inflammatory airway disease that is characterized by airway hyper reactivity and mucushypersecretion that result in intermittent airway obstruction. The incidence of allergic asthma hasalmost doubled in the past two decades. Although, precise causative mechanism of asthma isunknown, but several mechanisms have been proposed that is immunological, pharmacologicaland genetic mechanisms, and airway and neurogenic inflammation. The inflammatory processobserved in the asthmatic patients is the final result of a complex network of interactions betweenvarious immunological cell lineages, its mediators and secreted substances. Thus, among themechanisms proposed, the immunological one plays a key role. Through this article, we havetried to provide some insight into immunological mechanisms in pathogenesis of asthma.