We demonstrate a novel PNP bipolar junction transistor based optical phase-shifter on Si-photonic foundry platform. It exhibits a small static power consumption for p phase-shift (Pπ: 3mW), small driving-voltages (Vπ:0.1 V), fast switching time (rise/fall <1.19/0.6ns), and very-low power consumption (0.7mW) during dynamic operations.