This　paper　presents　U-Pb　zircon　geochronology,　petrology,　and　major　and　trace　elements　of　Cretaceous　felsite　porphyry　veins　in　western　Fuzhou　basin,　Fujian　Province.　These　data　were　used　to　investigate　the　genetic　relationship　between　felsite　porphyry　and　Fuzhou　composite　granite　body.　Felsite　porphyry　shows　purplish　gray　color　and　is　mainly　composed　of　orthoclase　phenocrysts,　and　the　well-developed　flow　structure　is　present　on　the　margin.　Felsite　porphyry　veins　have　a　NE-trending　strike　and　intruded　into　Fuzhou　composite　granite　body.　Felsite　porphyry　shows　the　features　of　calc-alkali　and　I-type　granites,　with　the　emplacement　age　being　97.4Ma;　it　was　formed　in　the　transition　period　between　early　Fuzhou　composite　granite　body　(111~100Ma)　and　late　Fuzhou　composite　granite　body　(95~90Ma).　The　geochemical　characteristics　between　the　above　three　phase　rock　types　present　a　gradually　changed　transitional　relation　on　the　time　scale.　That　is,　this　felsite　porphyry　is　the　product　of　the　tectonic　regimes　conversion　between　Early　and　Late　Cretaceous　in　southeastern　China.　The　authors　thus　hold　that　the　transformation　age　may　be　97Ma.　©　2019,　Science　Press.　All　right　reserved.