The resistance to antimicrobial agents among Staphylococci is an increasing problem. This has leads to resume interest in the usage of antibiotics to treat Staphylococcus aureus (S.aurues) infections. The main aim of this study was to isolate S. aureus from different 150 clinical samples such as blood, urine, pus, sputum and vaginal swab and to determine their susceptibility patterns by standard biochemical techniques and their antibiotic susceptibility tested by standard disk diffusion method. Detection of constitutive Clindamycin resistance was performed by D-test on a Mueller Hinton agar plate with a lawn culture of the isolates. On conclusion, observation of D- effect among some isolates provokes the necessities for development of new strategies.