Induction of general anesthesia with tracheal intubation is a routine procedure, but it can result in significant tachycardia, hypertension, and arrhythmia. Many approaches have been tried to blunt these circulatory responses. We selected randomly 45 adult patients undergoing elective surgery at Chungnam National University Hospital. They were divided into three groups. Group I: Thiopental 5 mg/kg (n=15) Group II: Fentanyl 3ug/kg+Thiopental 4mg/kg (n=15) Goup lII: Diazepam 0.1 mg/kg+Fentanyl 10ug/kg+Thiopental 2 mg/kg (n=15) Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and heart rate (HR) were measured for 5 min after intubation. The results were as follow. Group I-intubation caused a significant rise in SBP, DBP, MAP, HR, (p<0.01) but each parameter except H.R, returned to normal within 5 min. Group II-intubation caused a significant rise in SBP, DBP, MAP, HR (p< 0.01), but each parameter returned to normal within 3 min. Group III-after intubation caused little cardiovascular change, but decreases significantly preintubation (p<0.01) It is concluded that diazepam and moderate dose of fentanyl can effectively prevent postintubation hypertension and tachycardia.