Objective To investigate the median effective plasma concentration (Cp50) of propofol blunting cardiovascular responses to tracheal intubation with sufentanil at different targeted concentrations on anesthesia induction in elderly patients. Methods Ninty-four patients (60～79years) with an American Society of Anesthesiologists（ASA）physical status of Ⅰ～Ⅲ,undergoing scheduled surgery under general intubation were randomly allocated into one of four groups,Group A, B, C and D.The patients in Group A and Group B (60～69years) and the ones in Group C and Group D（70～79years） received sufentanil with a target effect concentration of 0.2ng/ml，0.3ng/ml，respectively. Induction of anesthesia was initiated by TCI sufentanil at target effect-site concentration and the target effect-site concentration of sufentanil was maintained stable before administration of propofol determined by up and down sequential test. At the moment of loss of consciousness, cis-atracurium 0.2mg/kg was administered. Intubation was performed for 3 min later. Results The Cp50 of propofol were 3.60, 2.03, 2.70 , 1.97μg /ml with 95% confidence interval of 3.34～3.86, 1.86～2.20, 2.56～2.84, 1.86～2.08μg/ml in Group A, B, C and D,respectively. Conclusion With the concentrations of sufentanil or age increased,the Cp50 of propofol decresed in elderly patients.