This paper presents a proposed means of frequency-tuning a magnetostrictive energy harvester(EH). This end may be accomplished by decreasing the distance between two permanent magnets (PM) located at free end of the cantilever and at the opposite, resulting in increase of a repulsive force between the PMs. The EH consists of a coil-wound Galfenol cantilever with PMs, a mover connected to the cantilever, and a rotating wheel with PMs. The rotating wheel driven by a motor provides a forced vibration to the EH. To direct inspection, It is noted that the maximum output voltage continually changes depending upon the the distance between the PMs And itmight therefore be deduced that the resonant frequency of the harvester may be adjusted to attain maximum, or optimal, voltage output. The rotational speed of the wheel (for the purpose of attaining maximum output voltage) is changed from 325 rpm to 265 rpm at a distance of 10 mm. It can be concluded that the practice of frequency-tuning with two PMs is a potentially positive application with respect to the EH.