[Abstract] Objective To investigate the effect of dexmedetomidine-propofol in suppressing the response of cough by equipotent boluses of fentanyl and sufentanil. Methods A total of 200 patients of ASA Ⅰ or Ⅱ, aged 18-65 yr, undergoing elective surgery were randomized into four groups of 50 each, using computer-generated random numbers. Group C1 or Group C2: normal saline 0.15ml/kg+ intralipid 0.1ml/kg; Group DP1 or Group DP2: dexmedetomidine 0.6μg/kg +propofol 1mg/kg. 1 min after receiving drugs mentioned before, patients in Group C1 or Group DP1 received i.v. fentanyl (4μg/kg) and patients in Group C2 or Group DP2 received i.v. sufentanil (0.5μg/kg). After fentanyl administration，the onset time and the severity of cough for 1 min were recorded. Severity of coughing was graded as mild (1-2), moderate (3-5) and severe (>5) based on the number of coughs. Induction of general anesthesia was continued with sufficient propofol and vecuronium 0.12mg/kg, then tracheal intubation was performed by a practiced anesthesiologist. BP and HR were recorded before infusion(T0), before intubation(T1) and after intubation(T2). Results The incidence of coughing was higher in Group C1 (20/50; 40%) or Group C2 (12/50; 24%) than in Group DP1 (0/50; P<0.01) or Group DP2 (0/50; P<0.01). However, no difference in the severity of cough between Group C1 and Group C2.(P>0.05). Compared with Group C1-2, SBP and DBP of Group DP1-2 was significantly increased in T1, but HR decreased significantly in T1-2(P<0.01); Compared with T0，SBP and DBP of four groups decreased significantly in T1, and HR of Group DP 1-2 decreased significantly in T2 (P<0.01); Compared with T1, HR of Group C1-2 increased significantly(P<0.01). Conclusion Pretreatment dexmedetomidine-propofol could completely suppress the response of cough by equipotent boluses of fentanyl and sufentanil, and the hemodynamics during general anesthesia induction and tracheal intubation were more stabler.