Twenty nine patients with sick sinus syndrome were treated from November, 1972 through July, 1976. Six cases had sinus bradycardia, 14 cases had sinoatrial block/sinus arrest and 9 cases had bradycardia-tachycardia syndrome. Twenty five patients received the implantation pacemaker with good result. There was found that an adequate pacing of the heart was effective for the control of the attack of tachyarrhythmia in the case with bradycardia-tachycardia syndrome.