Aspergillosis is a respiratory disease, the infection that most usually found in turkey, chicken, human beings, and other mammals; it less frequently found in pigeons, ducks, geese, and other domestic and wild birds. It caused by a species of fungus from the Aspergillus genus. Upon those farms, the disease may be endemic in chicken and turkeys. In wild birds, it seems too random and frequently only affects one bird at a time. Usually, 7 to 40 day old immature birds would exhibit it. Because Aspergillus spp. are so common, the disease can found wherever that the environment is suitable for its growth. Aspergillosis frequently results from Aspergillus fumigatus. However, a number of different mould species, including A. Flavus, A. niger, Rhizopus sp., Mucor sp, and Penicillium sp. may be blamed. Infection generally carried out through inhalation of spore-filled dust from infected dusty range areas. The disease has two different forms: acute and chronic. Acute form affects birds who have ingested huge amounts of spores, while chronic form affects birds with suppressed immune systems. For the diagnosis of Aspergillosis in poultry, which requires a range of diagnostic methods, culturing is essential because the clinical signs are non-specific. Aspergillosis cannot effectively treated; instead, prevention is the key to keeping the condition under control. Good management techniques, such as sanitation, avoiding damp litter or dirt and moldy or dusty feeds, providing adequate ventilation, and sterilizing feed and water systems, should use to prevent and control the disease.