Lawu　and　Yaguila　are　two　Pb–Zn　skarn　deposits　in　the　eastern　Nyainqêntanglha　metallogenic　belt,　central　Lhasa　subterrane,　Tibet.　The　genesis　of　Pb–Zn　deposits　in　this　belt　and　the　crustal　processes　leading　to　their　formation　remain　ill-constrained,　mostly　because　of　the　lack　of　precise　mineralization　ages.　We　integrate　textural　information,　geochemistry,　and　in-situ　garnet　U–Pb　geochronology　to　constrain　the　timing　and　genesis　of　Pb–Zn　mineralization.　Garnets　from　the　two　deposits　display　oscillatory　compositional　zoning　(And14Gr86　to　And100)　and　contain　variable　U　contents　(0.07–5.3　ppm).　Aluminum-rich　garnet　displays　a　chondrite-normalized　rare　earth　element　(REE)　fractionation　pattern　in　which　LREEs　are　depleted　relative　to　flattish　HREE　segments.　In　contrast,　Fe-rich　garnet　shows　LREE-enriched,　relatively　HREE-poor　patterns　with　positive　Eu-anomalies.　Uranium　concentration　is　correlated　with　total　REE　and　Fe　components　in　garnets,　implying　that　U　incorporation　is　largely　controlled　by　coupled　substitution　mechanisms.　The　same　garnets　also　contain　measurable　contents　of　other　metals　(up　to　hundreds　of　ppm),　such　as　Sn,　W,　and　In.　The　distribution　and　fractionation　of　major　and　trace　elements　in　zoned　garnets　record　periodic　fluid　pluses　with　different　compositions　during　hydraulic　fracturing.　The　new　garnet　U–Pb　data　show　that　the　Yaguila　deposit　formed　between　68.5　±　3.4　and　65.0　±　4.7　Ma,　and　the　Lawu　deposit　formed　at　54.6　±　2.9　Ma.　Within　the　geochronological　framework　of　igneous　rocks　and　Pb–Zn　mineralization　in　the　Nyainqêntanglha　metallogenic　belt,　the　new　garnet　ages　suggest　a　magmatic-hydrothermal　origin　for　related　mineralization,　with　the　causative　magma　likely　derived　from　partial　melting　of　ancient　continental　material　due　to　rollback　and　subsequent　breakoff　of　the　Neo-Tethys　oceanic　slab　during　India–Asia　continental　collision.　This　study　highlights　the　opportunities　offered　by　garnet　U–Pb　dating　for　elucidating　the　formation　age　and　ore　genesis　of　base　metal　skarn　systems.　©　2023　The　Author(s)