In this letter, we present a photonics integrated piezoMEMS (PipMEMS) platform for next-generation MEMS. We demonstrate on-chip optical transduction of a piezoMEMS structure. We use a heterogeneous 3D-bonding approach to integrate silicon photonics interrogator chip and lead-zirconate-titanate (PZT)-based MEMS device. We report on-chip measurements of three resonance modes of the PiezoMEMS beam that shows an excellent agreement with conventional laser Doppler vibrometer measurement. We also demonstrate measurement in a vacuum with one order of magnitude improvement in the quality factor of the fundamental resonance mode.