Aneurysm is an outpunching and dilation of blood vessel wall and generally can occur at any point of cardiac and peripheral vasculature: However, it is mainly formed in abdominal and thoracic parts of aorta, and in brain near arterial bifurcations of Willis circle. Risk of rupture is low in intracranial aneurysms. Aneurysm rupture is the most common cause of non-traumatic subarachnoid hemorrhage, a devastating event that carries high rates of mortality, morbidity and disability as well as a high health care cost. Thus, aneurysm treatment starts immediately after first recognition. Two types of treatment take place for intracranial aneurysms i.e, open surgery, and endovascular treatments. Although the second option is less risky, both methods can cause permanent disabilities during or after surgery. This work is devoted to find a way for prognosis of aneurysm rupture by employing hemodynamic parameters proved by researchers that have impact on growth and rupture of intracranial aneurysms. Wall Shear Stress (WSS) and Oscillatory Shear Index (OSI) are main hemodynamic parameters which are measured in this work. 3D geometries are made from CT Angiography scan images. Total of 26 patients with well-known aneurysm condition are studied. Including 12 cases of stable aneurysm and 14 cases of ruptured aneurysm. Aneurysm geometry is reconstructed and imported to simulation software after proper mesh generation. Steady state simulation of blood flow in aneurysm is performed and results are used for transient analysis. Pulsatile inflow boundary condition from previous measurements by Pc-MRI technique, is used for inlet velocity. Windkessel condition is defined for outflow boundary condition which considers the waveform pressure in vessels and structured tree of them. This boundary condition predicts the pressure from vessel wall properties and flow condition. WSS and OSI are calculated for further analysis. A single procedure is defined for integrating these parameters. After these integrations, all parameters are divided by their corresponding values from specific inlet length. First glances on dimensionless values of WSS and OSI showed that Ruptured aneurysms will result in lower WSS and higher OSI in comparison to un-ruptured ones. Mean value and standard deviation of each group of patients are calculated. Results demonstrate that WSS of unruptured aneurysms are five times larger than that for the other group. 90 percent confidence interval is also calculated for both groups. If this procedure is performed on a patient with known condition, the results will be in the range confidence interval of 90 percent. For defining the risk of rupture, a logistic regression method was used. This method reports risk of rupture by a single number between 0 and 1. Coefficients of logit function is calculated for each group. These functions for each parameter will help specialists to decide whether aneurysm rupture risk is high or low. Eventually treatment options can take place only if risk of aneurysm rupture is high. Key Words: Intracranial aneurysm, Rupture, Risk factor, Mechanisms.