Turbocharger is used to increase the efficiency of an engine. In the turbocharger, a centrifugal compressor is used. Centrifugal compressor failure has been a main issue in recent years. The failure of the centrifugal compressor is because of surge and stall. Surge occurs because pressure at the receiver is greater than the pressure at the compressor. So, gas flow will reverse and surge occurs. This work-study is based on reducing surge and stall. We can prevent the tendency of surge and stall by changing the factors affecting the change in pressure. We can change the pressure by changing the density of gas, number of impellers, impeller diameter, inlet and volute geometry and flow regulation. Hence, in this paper, we perform the CFD analysis of the centrifugal compressor by changing the geometry. © 2018 Totem Publisher, Inc. All rights reserved.