The　mafic　microgranular　enclaves　(MMEs)　from　Mesozoic　intermediate-acid　magmatic　rocks,　widely　developed　along　the　Fujian　coast,　are　considered　to　be　the　results　of　large-scale　crust-　mantle　interaction　by　magma　mixing.　This　paper　is　based　on　zircon　U-Pb　chronology,　along　with　zircon　Hf　isotope　and　mineral　analyses　for　the　host　granite　and　MMEs　from　Langqi　Island,　in　order　to　investigate　the　magma　mixing　mechanism　of　the　Langqi　pluton　in　Fuzhou,　Southeast　China.　The　results　indicate　that　the　MMEs　were　emplaced　during　the　late　Early　Cretaceous　(98.9　+/-　2.2　Ma),　identical　to　the　age　of　the　granite　(100.1　+/-　1.1　Ma)　within　the　error　range.　The　zircon　epsilon　Hf(t)　values　for　the　granite　and　MMEs　are　in　the　ranges　of　-2.1　similar　to　0.0　and-1.7　similar　to+1.1.　The　zircon　Hf　isotope　data　indicate　that　both　the　granite　and　MMEs　were　predominantly　derived　from　the　ancient　crustal　basement　of　Cathaysia,　with　a　partial　mantle-derived　contribution.　The　An　values　of　plagioclase　phenocrysts　with　oscillatory　zoning　patterns　in　the　MMEs　show　oscillatory　changes　from　the　core　to　the　rim,　indicating　multiple　mixing　events　between　the　two　magmas　with　different　compositions.　Amphiboles　in　the　MMEs　show　characteristics　of　crust-mantle　contamination,　and　the　Ti　migrated　from　the　mafic　magma　with　high　concentration　to　the　felsic　magma　with　low　concentration　during　the　magma　mixing　process.　Biotites　in　the　host　rock　and　MMEs　belong　to　primary　biotite,　and　they　have　relatively　high　MgO　contents　(ave.　12.78　wt.%)　and　relatively　low　FeOT/(MgO　+　FeOT)　ratios　(ave.　0.56),　showing　characteristics　of　crust-mantle　contamination.　The　crust-mantle　magma　interaction　in　a　crystal,　mushy　state　played　a　significant　role　in　controlling　the　formation　and　evolution　of　the　Langqi　pluton.　The　magmatism　was　predominantly　sourced　from　mixing　between　the　mantle-derived　mafic　magma　and　the　crust-derived　felsic　magma　during　the　subduction　of　the　Paleo-Pacific　Plate,　resulting　in　the　formation　of　the　Langqi　doleritic　veins,　granites,　and　MMEs.