Abstract Background: Surgical site infection is one of the common healthcare-associated infections. According to the CDC, in 2015 the number of surgical site infections associated with inpatient surgeries was 110,800. In India. Surgical site infection is estimated to be 3-12% (Kumar A,2017, India). As the staff nurses are part of the health care team, their clinical competency in infection control is vital. Nurses during the transition to practice have a theory-practice gap, which can lead to a reduction in the quality of patient care and a reduction of clinical performance, leading to an increased rate of surgical site infection. The present study aimed to assess the level of knowledge of staff nurses regarding surgical site infection prevention. Methodology: A descriptive research design was selected to assess the knowledge of staff nurses regarding surgical site infection prevention. A non-probability convenience sampling technique was used to select 80 subjects, aged between 20-51 years and above. A structured questionnaire containing demographic variables and items on surgical site infection prevention was administered to assess the participants' knowledge levels. Results: The study findings showed that (54) 67.5% of staff nurses have a moderately adequate level of knowledge, (23) 28.7% have an inadequate level of knowledge, and (3) 3.8% have adequate knowledge on surgical site infection prevention with a mean score of 15.83 ± 3.285. Chi-square test shows that there is no statistical association between demographic variables and nurses' knowledge on surgical site infection prevention. Conclusion and Interpretation: The study concluded that from the study findings, 67.5% of subjects had moderately adequate knowledge with a mean score of 15.83. The result of the study shows that there was no significant association between the knowledge and selected demographic variables like age, gender, marital status, educational qualification, working area, working experience, or any training undergone on infection control. Therefore, a lack of staff nurses' knowledge of surgical site infection prevention may lead to an increase in the surgical infection rate.