In the modern practice of general anesthesia, endotracheal intubation is routinely used for controlled ventilation. To facilitating intubation, succinlycholine is the most valuable muscle relaxant. But succinylcholine has many untoward reactions such as elevation of intraocular pressure, increased plasma potassium, increased intragastric pressure, bradycardia and the development of postperative muscle pain, etc. Several attempts have study was intended to determine adequate doses of gallamine triethiodide for endotracheal intubation in patients to avoid the development of bradycardis. The authors measured the heart rate just beofre, immediately after and 5 minutes after intubation. The total number of patients in this study was 67, and the patients were divided into five groups: Group 1: consisting of 10 patients, receiving 1.5 mg/kg of gallamine triethiodide. Group 2: of 10 patients, receiving 2.0 mg/kg of gallamine. Group 3: of 22 patients, receiving 2.5 mg/kg of gallamine. Group 4: of 15 patients, receiving 3.0 mg/kg of gallamine. Group 5: of 10 patients, receiving 3.5 mg/kg of gallamine. The authors tried to choose the least difficult intubation after gallamine triethiodide, the amount administered and the patient's reaction to stimulation. The conclusions are summarized as follows: 1) The adequate dose of gallamine triethiodide for endotracheal intubation is 2.5mg/kg. 2) The duraion of action of gallamine triethiodide is dose dependent. 3) Increase of heart rate in each group is significant after gallamine triethiodide.