A naturally occuring lymphoprolifrative neoplastic disease resembling reticuloendotheliosis was observed in one Flock of Egyptian pigeon (Assiut governorate). The neoplastic mass were detected mainly in the liver. Histopathologically revealed pleomorphic prolifrative infiltration with dark staining large cells, lymphocytes of different sizes, reticulum like cells, as well as mature and immature mononu clear cells. Histochemical studies revealed intracytoplasmic inclusion bodies. Based on the histopahological and histochemical studies, this lymphoprolifrative neoplastic disease may be reticuloendotheliosis.