Centrifugal compressors play an important role in many industries. Improving the efficiency of centrifugal compressors and extending their range has been an important subject for both engineers and researchers working in the turbomachinery field. This paper discusses the optimization of Eckardt O impeller through changing its blade angles distribution to increase its efficiency. the optimization process is performed using an automated procedure performed within ANSYS workbench. The geometry is parameterized using ANSYS design modeler, the mesh is generated using ANSYS Turbogrid and steady flow CFD results are obtained using ANSYS CFX. Optimization by genetic algorithm is done using a surrogate model generated through a sample of designs selected through Design of experiments “DOE" sampling. The performance of the optimized and the original designs are compared both qualitatively and quantitatively, the optimized design efficiency successfully increased from 87.994 % to 88.481% based on CFD results.