Background: this study examines the incidence, characteristics, and risk factors of surgical site infections (SSIs) after spine surgery and evaluates the efficacy of a preventive intervention. Methods: this was a quasi-experimental pretest/posttest study in patients undergoing spinal surgery in an orthopedic surgery department from December 2014 to November 2016. Based on the results of the study, we revised the preventive protocol with modification of wound dressing, staff training, and feedback. SSI rates were compared between the pre-intervention (December 2014 to November 2015) and post-intervention (December 2015 to November 2016) periods. The risk factors were analyzed using univariate and multivariate analyses. Results: of the 139 patients included, 14 cases of SSI were diagnosed, with a significant decrease in the incidence of SSIs from the pre-intervention period to the post-intervention period (19.4% vs 2.6%; P = .001). The etiology was known in 13 cases, with enteric flora being predominant in the pre-intervention group. Univariate analysis showed that age, body mass index, days until sitting and ambulation, and incontinence were statistically significant risk factors. After multivariate analysis, only body mass index and days until ambulation remained significant. When the effect of intervention was adjusted with other risk factors, this variable remained statistically significant. Conclusions: an intervention that includes modification of wound dressing and early mobilization, as well as staff awareness training, monitoring, and feedback, allowed a significant reduction in the incidence of SSI following spinal surgery, particularly infections caused by enteric flora.