Surgical site infection presents as a significant problem that limits the potential benefits of surgical interventions. This study is to investigate risk factors for postoperative SSI in patients with Crohn's disease receiving definitive bowel resection. A case-control study including 49 patients with SSI and 105 patients without SSI was performed. Demographics, clinical characteristics, laboratory information, medical and surgical data were compared between groups. Significant elements were subsequently brought into logistic regression analysis for further identification. Patients with SSI exhibited higher tobacco usage rate (p = 0.03), lower preoperative hemoglobin (p = 0.02) and pre-albumin level (p = 0.02). Bowel penetration instead of stricture was more frequent in patients with SSI (p = 0.04). Longer duration of operation (p = 0.03) and higher intraoperative lactate level (p = 0.02) were observed in patients with SSI. Logistic analysis identified that preoperative pre-albumin (95% CI: 0.2~0.7; OR = 0.5; p = 0.03), duration of operation (95% CI: 2.3~9.5; OR = 3.8; p = 0.03) and intraoperative lactate level (95% CI: 1.7~7.2; OR = 3.4; p = 0.04) were associated with postoperative surgical site outcome. Our data has identified that lower preoperative pre-albumin, longer duration of operation and higher intraoperative lactate level are risk factors for SSI in patients with Crohn's disease receiving definitive bowel resection.