Subarachnoid hemorrhage has a lot of dangerous complications, especially re-bleeding and vasospasm, which are major causes of death and disability. Mortality is often related to the acute effects of subarachnoid hemorrhage. Objectives: study clinical characteristics, subclinical characteristics and causes of subarachnoid hemorrhage. Complications and complication management of subarachniod hemorrhage. Subjectives and Methods: Cross sectional prospective study on 96 patients who suffered from subarachnoid hemorrhage admitted to the Stroke Unit, Neurology Department, Bach Mai Hospital from January 2009 to October 2010. Results and Conclusions: There were 38 females and 58 males with the average age of 46.13, age ranged from 45 to 54 accounted for the highest proportion (46.9 percent). Typical clinical features were: headache (100 percent), meningeal syndrome (95.8 percent), nausea and/or vomiting (59.4 percent), depression of consciousness (55.2 percent). Sabarachnoid hemorrhage due to the rupture of intracranial saccular aneurysm is 79.2 percent, and Arteriovenous malformation (8.3 percent)... As for complications, re-bleeding is the most dangerous one (16.7 percent), cerebral spasm cause of cerebral ischemia and infarction take up the highest proportion (37.5 percent), acute and subacute hydrocephalus (12.5 percent), hyponatremia (13.5 percent) and seizures (6.25 percent).