[en] Highlights: • Switchable photoelectrochemical response in Pb(Zr_0.2Ti_0.8)O₃ epitaxial films was detected for the first time. • Switchable photocurrent response can solely be controlled by ferroelectric polarization direction. • Switchable photocurrents present high repeatability and non-volatile. • The PZT/SRO electrode can be treated as a photoanode or photocathode. Ferroelectric semiconductors splitting water reactions have presented a new paradigm in improving conversion efficient of solar energy into electricity or fuel. Here, we show the switchable photoelectrochemical response controlled by ferroelectric polarization in (101)-oriented Pb(Zr_0.2Ti_0.8)O₃ (PZT) epitaxial films prepared on the (110) SrTiO₃ substrate with SrRuO₃ as bottom electrodes. Photoelectrochemical (PEC) measurements exhibit that the switchable photocurrent response can be observed in the PZT/SRO heterostructures photo-electrode. Moreover, under illumination, the switchable photocurrents of the PZT/SRO electrode present high repeatability and non-volatility, which only depend in the ferroelectric polarization direction of the PZT film. The result indicates that the PZT/SRO electrode may be as a photoanode or photocathode only through poling treatment with the external electric field. We suggest that the internal electric field and depletion region by ferroelectric polarization at the PZT film is mainly responsible for the switchable PEC effect. The study indicates that this ferroelectric photo-electrode material may have potential applications in solar water splitting, and specially in the PEC sensing and any other smart photo-responsive systems.