The data for subarachnoid hemorrhage (SAH) from the Japanese Standard Stroke Registry Study (JSSRS) were analyzed to evaluate the incidence of SAH according to age, neurological grading and outcome, and outcome of surgical clipping, for comparison with the International Subarachnoid Aneurysm Trial (ISAT). From the JSSRS data, the peak incidence of SAH was the sixth decade in males and the eighth decade in females. The overall mortality was 22%, and good outcome, better than 2 on the modified Rankin Scale (mRS), at discharge was achieved in 58% of cases. Radical treatment was performed in 62.6% of all SAH cases, 58.7% with surgical clipping and 3.2% with endovascular coiling. Poor outcome, worse than 3 on the mRS, occurred in 26.6% of patients under 60 years, 47.3% between 60-69 years, 54.2% between 70-79 years, and 72.9% 80 years or over. From the ISAT data, 88% of patients were in grades 1-2 of the World Federation of Neurological Surgeons (WFNS) grading system in both surgical clipping and endovascular coiling groups, 94% in grades 1-3, and 98% in grades 1-4. Poor outcome, worse than 3 on the mRS, at 2 months occurred in 25.4% and 36.4% of patients with endovascular coiling and surgical clipping, respectively. Limiting the patients in the JSSRS to WFNS grades 1-2 showed poor outcome, worse than 3 on the mRS, occurred in 12.8%, and in grades 1-3 and 1-4 occurred in only 16.3% and 23.0%, respectively.