Fungi inhabit nearly all terrestrial environments. In this regard, the interiors of human dwellings and workspaces are no exception. The mould flora of human-inhabited indoor environments consists of a distinctive group of organisms that collectively are not normally encountered elsewhere. In our study of house dust flora mainly found Aspergillus species some are identified as Aspergillus niger, Aspergillus fumigatus and Aspergillus flavus.The Aspergillus species or their spores can cause allergic reactions. Peopole with severe asthma are often sensitive to Aspergillus and can suffer asthma attacks because of the spores.  Aspergillus species can infect people and animals and begin to grow inside them, especially in the lungs. Aspergillus infections are categorized in the group of diseases called Aspergillosis.