The main goal of current study was to investigate the prevalence of coccidiosis in broiler farms in Hamedan province, western Iran. Chicks and fecal samples were collected in all of the 220 broiler farms in this region. All viscera were examined for gross pathological changes. The mucosa of small intestine and the caeca were examined for the presence and identification of parasitic forms using parasitology methods. The overall rate of coccidiosis was 31.8%; E. acervulina (75.7%), E. tenella (54.3%), E. necatrix (28.6%), and E. maxima (20%) were determined. Mixed infections were observed in all of the positive farms. There was a statistical significant difference ( < 0.05) among infection rate and age groups, dysentery, history of colibacilosis and clostridiosis in farm, and history of coccidiostats consumption, unlike to breed ( > 0.05). This is the first report of coccidiosis rate in broiler farms in this region. Further additional researches and design control strategies for improving management in farms are necessary
