Abstract: Objective To explore the relationship between perioperative insulin resistance and hepatobiliary & pancreatic surgical trauma. Methods Total of 186 patients underwent hepatobiliary & pancreatic surgery in our department between January 2014 and December 2015 were enrolled and divided into 3 groups according to the POSSUM scoring system:mild trauma group (OSS ≤ 7), moderate trauma group (OSS=8-10) and severe trauma group (OSS> 10). The patients' preoperative general characteristics, physiological scores and insulin sensitivity at different time points between three groups were analyzed and compared. Results No significant difference was found in patients' age, gender, BMI index and preoperative physiological scores between the three groups. The surgical trauma scores were 9.6±1.7 in mild trauma group, 12.4±2.3 in moderate trauma group and 16.3±2.8 in severe trauma group, and the difference between each group was statistically significant (P< 0.01, respectively). Insulin sensitivity decreased in three groups, and nadir occurred at 24 h after operation. It decreased by 26.2% in group C, which was significantly higher than 13.4% in group A and 15.1% in group B (P< 0.01, respectively). In addition, the insulin sensitivity level returned to the preoperative level in group A and group B at 7th day after operation, while no same trend showed in group C, and the difference was statistically significant (P< 0.01, respectively). Conclusion Insulin resistance degree is positively correlated with the surgical trauma severity. The insulin resistance peaks at 24 h after operation, then returns to normal with patients' recovery. The duration of insulin resistance extends with the increasing of surgical trauma severity.