By　maintaining　high　piezoelectric　coefficients　(d33),　increasing　the　depolarization　temperature　is　the　key　to　constructing　high-performance　high-temperature　piezoceramics.　Unfortunately,　so　far,　no　piezoceramic　has　been　found　that　still　has　ad33value　above　700　pC　N−1byin　situtesting　at　a　high-temperature　of　400　°C.　For　popular　0.36BiScO3-0.64PbTiO3ceramics　with　a　MPB　structure,　thein　situquasi-staticd33value　at　400　°C　is　only　405　pC　N−1.　Herein,　a　new　strategy　to　enhance　perovskite　lattice　distortion　to　obtain　oxides　with　excellent　high-temperature　piezoelectricity　has　been　proposed.　By　introducing　Bi(Zn0.5Hf0.5)O3to　enhance　lattice　distortion　of　a　(1　−x)BiScO3-xPbTiO3matrix,　a　ternary　systemzBiScO3-xPbTiO3-yBi(Zn0.5Hf0.5)O3(zBS-xPT-yBZH)　was　designed.　A　record-highin　situquasi-staticd33value　of　726　pC　N−1at　400　°C　is　achieved　in　a　0.355BS-0.635PT-0.01BZH　composition.　Structural　analysis　confirmed　that　the　introduction　of　highly　tetragonal　Bi(Zn0.5Hf0.5)O3can　enhance　the　lattice　distortion　and　the　sample　annealed　at　400　°C　still　maintains　a　stable　domain　configuration.　Moreover,　a　high-temperature　piezoelectric　energy　harvester　is　manufactured　from　the　optimal　material,　and　exhibits　excellent　high-temperature　power　generation　capacity,　and　a　10　μF　commercial　electrolytic　capacitor　can　be　easily　charged　to　0.9　V　in　40　s　at　400　°C.　This　work　demonstrates　thatzBS-xPT-yBZH　ceramics　have　great　potential　for　application　in　extreme　high　temperature　environments,　and　pave　the　way　for　obtaining　high-quality　high-temperature　piezoelectric　materials.　©　The　Royal　Society　of　Chemistry　2021.