In recent years infections caused by bacteria resistance to multiple antibiotics have been a significant problem. Methicillin resistant Staphylococcus aureus (MRSA) has been troubling hospital services all over the world. Another highly infectious disease caused by the species of Salmonella. The disease results from a true food infection because the bacteria can multiply and invade the intestinal mucosa. Effectiveness of three antibiotics was checked in the study: chloramphenicol, tetracycline and erythromycin were tested against Staphylococcus aureus and Salmonella typhimurium using agar-well diffusion technique. Tetracycline is highly effective against S. aureus and resistant against erythromycin. S. typhimurium against chloramphenicol in comparison to tetracycline and erythromycin.