Cerebral vasospasm causes permanent neurolological deficit or death occurance in 13% of clinical cases. Peak frequency is from 8-10th day after SAH. The purpose of this study is factor analysis that may have influence on vasospasm development , as well as predictor determination. The study is prospective and analysis 192 patients treated in Institute of Neurosurgery, Clinical Centre of Serbia, Belgrade. The majority of patients were admitted in hospital in first four days after SAH, and 184 had GCS over 7. Univariate methods of factor analysis were used, and for significance of predictors influence testing multivariante regression analysis was used. Vasospasm occurred in 22,40% of all cases. No relationships have been found between sex, age, previous hypertension, timing of surgery, appearance of hydrocephalus and intracerebral hematoma, hypertermia or mean arterial blood pressure, with occurrence of cerebral vasospasm. Factors with significantly associated with the occurance of vasospasm were: hearth disease, hypernatriemia, Hct, clinical grade on admission as well as preoperative clinical grade and Fisher CT scan grade. In the first four days after SAH, Fisher scan grade, preoperative clinical grade and Hct, appeared as predictors. After four days, clinical grade on admission and hypernatiemia, showed as poredictors.