BACKGROUND: This study was undertaken to evaluate the hemodynamic response of midazolam-thiopental coinduction technique compared with thiopental or midazolam induction after tracheal intubation. METHODS: 60 patients were divided into 3 groups. Group I thiopental 5 mg/kg induction groups: Group II, midazolam 0.2 mg/kg induction group: Group III 2 mg/kg of thiopental was injected intravenously to each patient 2min after 0.02 mg/kg of midazolam injected. After tracheal intubation, blood pressure and heart rate were measured for 5 minutes at 1 minute interval. Results: There were not significant differences in systolic, diastotic, mean arterial pressure and heart rate in 3 groups. CONCLUSIONS: Low dose midazolam-thiopental coinduction can be a useful method for induction because of same hemodynamic changes as to thiopental or midazolam alone.