In this study, we investigate the piezoelectric modulation of magnetic properties in an Fe/CoO bilayer grown on a Cr-buffered PMN-PT(001) substrate. An initial application of an electric field across the substrate has induced a non-volatile change in the coercive field of Fe/CoO. Subsequent voltage applications further modified the coercive field of Fe/CoO, maintaining the non-volatile effect below the blocking temperature of CoO. In contrast, no piezoelectric influence on the magnetic properties was observed in the Fe single layer grown on Cr/PMN-PT. X-ray magnetic linear dichroism measurements confirmed that the piezoelectric-driven modulation of magnetic behavior in Fe/CoO bilayer is primarily governed by changes in the magnetic state of the CoO film.