From the viewpoint of AdS/CFT correspondence, we investigate the holographic thermalization process in a four dimensional Einstein-Maxwell-axions gravity theory, which is considered as a simple bulk theory dual to a boundary theory with momentum relaxation. We probe the thermalization process using the equal time two-point functions and the entanglement entropy with the circle profile. We analyze the effects of momentum relaxation on the process in details and results show that the momentum relaxation gives longer thermalization time, which means it suppresses the holographic thermalization process. This matches the properties of the quasi-normal frequencies for the bulk fluctuations which the frequency violates from zero mode more profoundly for stronger momentum relaxation. We claim that is reasonable because the decay of the bulk fluctuations holographically describes the approach to thermal equilibrium in the dual theory.