The prevalence of suppurative arthritis in one hundred sheep from both sexes and different ages were studied. Aspiration of synovial fluid from knee joint of animals showed signs of lameness with reluctant to move in addition to decrease in the body weight and loss of appetite. Physical and bacterial examination of the synovial fluid was revealed green color, turbid and containing pus. Mucin clot showed difference in degree of clotting, and increased number in leukocyte, neutrophile but decreased in lymophocytes and monocyte. The result showed that Streptococcus dysagalactiae was predominate 61.1% while Arcanobacterium pyogenes and Pseudomonas aeruginosa were the less 5.5%, also the result showed that all the strains were more sensitive to the Ciprofloxacin. This study is considered to be the first attempt to isolate bacteria from Sheep joints in Mosul-Iraq.