Induction of general anesthesia with tracheal intubation is routine procedure but causes significant tarchycardia and hypertension. Many approaches have been tried to attenuate these circulatory response. The effects of small dose fentanyl on arterial pressure and heart rate increase during intubation were studied in 40 normotensive patients, who were randomly allocated to two groups, receiving saline (Control group) or fentanyl 2ug/kg (Fentanyl group), in a double blind fashion during anesthetic induction with thiopental 5mg/kg. Systolic, diastolic, mean arterial pressure and heart rate were measured and rate pressure product was calculated. All parameters were significantly different between two groups (p<0,05) and control group was significant increase in blood pressure and heart rate compared with pre-induction value but fentanyl group was relatively small changes of blood pressure and heart rate (p<0.01). After tracheal intubation, incresed blood pressure was returned to pre-induction value within two to three minutes in fentanyl group but heart rate was not returned pre-induction value within 5 minutes. Dose of fentanyl that are low enough to cause any side effects of drug itself, no notable side effects were observed during study and recovery.