OBJECTIVE：To explore the effects of different doses of sufentanil on hemodynamics and postoperative stress response of children with congenital heart disease in cardiac surgery anesthesia. METHODS：40 children underwent ventricular septal defect repair in our hospital were divided into group A，B，C and D with 10 cases in each group according to the dose of sufentanil. Groups A，B，C and D were given intravenous injection of sufentanil（0.6，0.8，1.0，1.2 μg/kg）respectively during anesthesia induction. Heart rate（HR）and systolic blood pressure（SBP）of 4 groups were recorded before induction（T1），after induction （T2），intubation（T3），2 min after intubation（T4），5 min after intubation（T5），and 10 min（T6）after intubation. The contents of acetylcholine（ACH），cortisol，glucagon，IL-6 and lactic acid were recorded when getting into the operating room（t1），after intubation（ t2），after spliting the sternum（t3），before rewarming（t4），10 minutes after the shutdown the CPB（t5）and 24 h after operation（ t6）. RESULTS：There was no significant differences in HR and SBP between 4 groups at T1（P＞0.05）； but there was statistically significant difference between 4 groups at T2-T6（P＜0.05）. There was no statistical significant difference in ACH，glucagon， IL-6 and lactic acid between 4 groups at T1（P＞0.05）；but there was statistically significant difference between 4 groups at T2-T6 （P＜0.05）. There was no statistically significant difference in cortisol between 4 groups at T1-T4（P＞0.05）；but there was statistically significant difference between 4 groups at T5-T6（P＜0.05）. CONCLUSIONS：During pediatric cardiac surgery anesthesia，the concentration of sufentanil kept in 1.0 μg/kg is the most suitable，and has small effect on hemodynamics and postoperative stress response.