The effect of fentanyl on arterial pressure and heart rate during laryngoscopy and intubation was studied in 40 adult normotensive patients. Two groups of 20 patients were observed. Patients received thiopental sodium 5 mg/kg (contal group) or fentanyl 2 ug/kg with thiopental 5 mg/kg (fentanyl group) for induction of anesthesia. The changes of systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and heart rate (HR) were measured during the preinduction period, before thiopental (or thiopental+fentanyl), after succinylcholine, immediately after intubation and 5 minutes after intubation. The values were compared with preinduction control values. The results were as follows: The contro#l group showed a significant inerease of SBP, DBP and MAP (p<0.001) but no significant increase was noted in the fentanyl group with tracheal intubation. DBP and MAP returned to normal within 5 minutes and SBP decreased significantly (p<0.05). Significant heart rate elevation following intubation was observed in both groups. It is suggested from the above results that pretreatment with fentanyl 2 g/kg reduce the blood pressure elevation following intubation but dose not prevent the elevation of heart rate.