The respiratory system serves as the principal site of infection for many pathogens that cause chronic diseases in birds, and respiratory problems are the primary cause of financial losses in the poultry industry. This study aimed to isolate different bacterial pathogens that affected broiler chicks. Samples were collected from freshly dead and diseased chicks that suffered from respiratory manifestations associated with diarrhea. These samples were under test (n=6433, 4628, 4613, 6377, and 4713) for isolation of Salmonella, E. coli, Klebsiella, Proteus, and Pseudomonas, respectively. Samples collected from broiler chicks aged from one to 35 days were collected from Wahat, Regwa (Cairo 3 A company), and external farms, in Egypt. The prevalence of isolated bacterial pathogens was 9%, 65.3%, 8.8%, 1%, and 3.2% for Salmonella, E. coli, Klebsiella, Proteus, and Pseudomonas, respectively. All the isolated bacterial pathogens were identified biochemically by using the Indole test, Methyl red test (MR), Voges-Proskauer test (VP), Citrate utilization test, Catalase test, Oxidase test, Hydrogen sulfide production test, Urease production test, Sugar fermentation, nitrate reduction test, triple sugar iron agar, and Lysine decarboxylase test.