The　development　of　high-performance　near-infrared　(NIR)　phosphor-converted　LEDs　(pc-LEDs)　demands　phosphors　that　exhibit　broadband　emission,　high　quantum　yield,　and　excellent　thermal　stability-a　combination　that　is　rarely　achieved　in　existing　systems.　Herein,　we　report　a　novel　Cr3+-activated　Y3MgAl3SiO12　(YMASO)　phosphor　synthesized　via　an　efficient　sol-gel　route.　Crystal　field　analysis　reveals　the　coexistence　of　Cr3+　ions　in　both　strong-field　[AlO6]　and　weak-field　[MgO6]　octahedra,　facilitating　broadband　emission　with　a　full　width　at　half　maximum　(FWHM)　of　167　nm　through　dual-site　engineering.　The　optimized　YMASO:0.015Cr　exhibits　a　remarkable　internal　quantum　efficiency　of　92.73　%　and　demonstrates　favorable　thermal　stability.　When　integrated　with　a　410　nm　blue　LED　chip,　the　fabricated　NIR　pc-LED　achieves　an　output　power　of　27.55　mW　and　a　photoelectric　conversion　efficiency　of　8.7　%　at　100　mA,　surpassing　most　reported　chromium　(Cr3+)-based　systems.　This　positions　YMASO:Cr　as　a　promising　candidate　for　high-efficiency　NIR　pc-LED　applications.