Objective: In this study, the authors accessed the prevalence of bacteria in surgical site areas of abdominal operated patients at six different time points of surgical procedure. Subject and method: 271 patients with abdominal surgery were classified clean and clean infected. The patients were bathed with disinfectant soap before surgery due to infection control department provides. Samples were taken from June to September 2012. Result: The results showed, among of 271 patients male/female ratio was 1.6, age ranged from 53.8 +/- 12.5. After taking bath, 20.7 percent of patients were negative for bacteria in comparison with 100 percent positive before taking baths (p0.001). And the number of bacteria were significantly reduced after taking baths such as S. aureus from 6.6 percent to 2.3 percent (p0.05), E. coli (16.2 percent to 3.2 percent, p0.001), Klebsiella sp (8.1 percent to 2.7 percent (p0.05). Conclusion: Although disinfection at operation site cannot kill all of the bacteria and contamination of the skin might occur during surgical procedure. But, the amount of bacteria significantly reduced in surgical site areas after taking bath.