The understanding and accurate prediction of the flow behavior in a Kaplan turbine are important to the design work enhancing the turbine performance including the elongation of the operation life span and the improvement of turbine efficiency. The present work concerns a stationary numerical investigation of an axial hydraulic turbine of the Kaplan type in order to study the influence of the numbers of stator and rotor blades on the flow behavior related to cavitation through the commercial code ANSYS CFX. The operating conditions of this axial turbine, similar to those encountered in a previous experiment, made it possible both to validate the numerical model and to identify the nominal operating regime. In addition, variations in the numbers of stator and rotor blades have shown observations regarding the influence of the numbers of stator and rotor blades on the cavitation phenomenon.