Subarachnoid hemorrhage (SAH) is rare in young adults and little is known about aneurysms in this subgroup. The effect of clinical and prognostic factors on the outcome based on the Glasgow Outcome Scale (GOS) scores and the predictors of unfavorable outcomes were analyzed in young adults with aneurysmal SAH. A retrospective review of the clinical parameters, including age, sex, hypertension, smoking status, hyperlipidemia, location of the cerebral aneurysm, size of the aneurysm, multiplicity, perioperative complication such as hydrocephalus, vasospasm, and hematoma, and Hunt and Hess and Fisher grading on presentation, was conducted in 108 young adults (mean age 34.8 years) managed at our institute. The outcome was classified based on GOS grading into unfavorable (GOS scores 1-3) or favorable (GOS scores 4 or 5). The overall mortality rate was 3.7% (4/108 patients). Univariate regression analysis for the outcomes at discharge found that age at the time of presentation, male sex, size of aneurysm, multiple aneurysms, hyperlipidemia, and poor Hunt and Hess and Fischer grades were associated with unfavorable outcome. Multivariate regression analysis found independent effects of sex, multiple aneurysms, size of aneurysm, and Hunt and Hess grade on the outcome at discharge. Size of aneurysm, presence of multiple aneurysms, Hunt and Hess grade, and hypertension were the predictors of outcome at mean 2-year follow up based on multivariate exact regression analysis. The multimodal approach with aggressive medical management, early intervention, and surgical treatment might contribute to favorable long-term outcomes in patients with poor expected outcomes.