One hundred diseased cases of pigeons (Columba livia) in Mosul city were examined, 67 birds (67%) showed pathological lesions in digestive system. Most of the gross and histopathological lesions occurred in intestine (29.3%) followed by oropharynx, liver, esophagus, crop, proventriculus, and pancreas the values (20.8%, 16.6%, 12.5%, 10.4%, 6.2%, 4.2%) respectively. Gross lesions of intestine showed severe tape worms infestation with petechial hemorrhage in some cases, histopathologically there were catarrhal enteritis, necrotic and hemorrhagic enteritis were less, and desquamation of mucosa with bacterial colonies. Gross lesions of oropharynx, esophagus and crop in most cases were yellow caseated masses or necrotic material. In some cases white diphtheritic membrane with thickening of mucosa in esophagus, crop and proventriculus were founded, petichial hemorrhage on the mucosa of proventriculus were less some cases. Histopathological lesions of oropharynx and esophagus were thickening of mucosa and presence of necrotic caseated foci on the submucosa. In crop there were epithelial hyperplasia and in some cases infiltration of inflammatory cells with cocobacilli bacteria and desquamation of epithelial cells were founded. In proventriculus desquamation and necrosis of epithelial cells of mucus glands with infiltration of inflammatory cells. Gross lesions in liver and pancreas were limited represented by enlargement and congestion, histopathologically coagulative necrosis of hepatic cells with cocobacilli bacteria, pancreas showed two types of inflammation one was non-suppurative and another was suppurative.