Mycoplasmas and Entrobacteracae could be isolated and identified from 213 living and 87 dead free flying birds and migratory Powis captured from Assiut Governorate. According to the growth precipitation, growth inhibition, and immuno-fluresence tests, M. gallisepticum, M. gallinarum, M. columbinum, A. laidlawii and untyped Mycoplasmas could be identified. On the basis of biochemical and serological tests, E.coli, Salmonella sp., Klebsiella, Protsus. Entrobacter, and unidentified types could be isolated. I could be concluded that free flying birds play a mechanical and biological role in transmission of Mycoplasmas and Entrobact eracee to poultry farms.