Solid-state　quantum　emitters　are　gaining　significant　attention　for　many　quantum　information　applications.　Hexagonal　boron　nitride　(h-BN)　is　an　emerging　host　material　for　generating　bright,　stable,　and　tunable　single-photon　emission　with　narrow　line　widths　at　room　temperature.　In　this　work,　we　present　a　facile　and　efficient　approach　to　generate　high-density　single-photon　emitters　(SPEs)　in　mechanically　exfoliated　h-BN　through　H-　or　Ar-plasma　treatment　followed　by　high-temperature　annealing　in　air.　It　is　notable　that　the　postannealing　is　essential　to　suppress　the　fluorescence　background　in　photoluminescence　spectra　and　enhance　emitter　stability.　These　quantum　emitters　exhibit　excellent　optical　properties,　including　high　purity,　brightness,　stability,　polarization　degree,　monochromaticity,　and　saturation　intensity.　The　effects　of　process　parameters　on　the　quality　of　quantum　emitters　were　systematic　investigated.　We　find　that　there　exists　an　optimal　plasma　power　and　h-BN　thickness　to　achieve　a　high　SPE　density.　This　work　offers　a　practical　avenue　for　generating　SPEs　in　h-BN　and　holds　promise　for　future　research　and　applications　in　quantum　photonics.　©　2024　American　Chemical　Society.