OBJECTIVE： To investigate the effects of target-controlled infusion of etomidate combined with remifentanil on indexes of immune and stress response in elderly surgery patients. METHODS： Totally 60 patients undergoing elective surgery were randomly divided into control group （n＝30） and observation group （n＝30）. Control group was given Propofol injection 1.5-2 mg/kg intravenously. Observation group was given Remifentanil hydrochloride for injection with pump volume of 0.5 μg/（kg·min）， and then target controlled infusion of Etomidate injection 0.1-0.3 mg/kg； the dose of etomidate increased by 0.05-0.1 mg/kg according to physical activity during surgery. Postoperative eye opening time， recovery time of orientation and extubation time were compared between 2 groups as well as the levels of immune indexes （CD4+， CD8+，CD4+/CD8+），stress response indexes [serum norepinephrine （NE）， adrenaline （E） and cortisol （Cor）]. The occurrence of ADR was recorded during surgery. RESULTS： Postoperative eye opening time， recovery time of orientation and extubation time in observation group were significantly shorter than control group， with statistical significance （P＜0.05）. Before surgery， there was no statistical significance in CD4+，CD8+ and CD4+/CD8+ between 2 groups（P＞0.05）. After surgery， CD4+ and CD8+ of 2 groups were significantly higher than before surgery， and the observation group was significantly higher than the control group， CD4+/CD8+ of 2 groups was significantly lower than before，and the observation group was significantly lower than control group， with statistical significance （P＜0.05）. Before surgery， there was no statistical significance in the levels of NE， E and Cor between 2 groups （P＞0.05）； after surgery， the levels of NE， E and Cor in 2 groups were significantly higher than before surgery， but the observation group was significantly lower than the control group， with statistical significance （P＜0.05）. There were no obvious adverse reaction occurred in 2 groups during the surgery. CONCLUSIONS： The target-controlled infusion of etomidate combined with remifentanil is ideal for perioperative anaesthesia in the elderly patients and effectively improves related immune indexes and stress response indexes with good safety.