Oxygen　vacancies　(OVs)　spatially　confined　on　the　surface　of　metal　oxide　semiconductors　are　advantageous　for　photocatalysis,　in　particular,　for　O2-involved　redox　reactions.　However,　the　thermal　annealing　process　used　to　generate　surface　OVs　often　results　in　undesired　bulk　OVs　within　the　metal　oxides.　Herein,　a　high　pressure-assisted　thermal　annealing　strategy　has　been　developed　for　selectively　confining　desirable　amounts　of　OVs　on　the　surface　of　metal　oxides,　such　as　tungsten　oxide　(WO3).　Applying　a　pressure　of　1.2　gigapascal　(GPa)　on　WO3　induces　significant　lattice　compression,　which　would　strengthen　the　W-O　bonds　and　increase　the　diffusion　activation　energy　for　the　migration　of　the　O　migration.　This　pressure-induced　compression　effectively　inhibits　the　formation　of　bulk　OVs,　resulting　in　a　high　density　of　surface-confined　OVs　on　WO3.　These　well-defined　surface　OVs　significantly　enhance　the　photocatalytic　activation　of　O2,　facilitating　H2O2　production　and　aerobic　oxidative　coupling　of　amines.　This　strategy　holds　promise　for　the　defect　engineering　of　other　metal　oxides,　enabling　abundant　surface　OVs　for　a　range　of　emerged　applications.　©　2025　American　Chemical　Society.