Surgical site infections are the most important problems of surgery. They increase morbidity, mortality, hospital stay and hospital costs. Infection occurring within 30 days after the operation if no implant is left in place or within 1 year if implant is in place is described as surgical site infection. These infections are classified into two categories; incisional or organ/space specific infections. Incisional infections are further divided as superficial or deep incisional infections. Development of surgical site infections is mainly dependent on type of micro-organism and patients’ factors related to host resistance. The endogenous flora of the patients’ skin, mucous membranes, or hollow viscera is the main source of microorganisms responsible for surgical site infections. Development of such infections can be influenced via a lot of risk factors such as nutritional status, diabetes, smoking, altered immune response, and length of preoperative stay, skin antisepsis, preoperative shaving, duration of operation, antimicrobial prophylaxis, operating room ventilation, inadequate sterilization, the presence of foreign material in the surgical site, and surgical techniques. With the improvement of some of these factors, risk of developing surgical site infections may be decreased. The aim of this study was to discuss the risk factors and prevention measures of surgical site infections in the lightening of current literature.