The widespread W-(Mo)-Sn-Nb-Ta polymetallic mineralization in Southeast (SE) China is ge- netically associated with Mesozoic highly fractionated granitic rocks. Such rocks have enigmatic mineralogi- cal and geochemical features, making its petrogenesis an intensely debated topic. To better understand the underlying magma evolution processes, petrography, garnet chemistry and whole-rock major and trace ele- ment data are reported for Jurassic highly fractionated granitic rocks and associated microgranite and aplite- pegmatite dikes from Macao and compared with coeval similar granitic rocks from nearby areas in SE China. Despite the fact that the most evolved rocks in Macao are garnet-bearing aplite-pegmatite dikes, the existence of coeval two-mica and garnet-bearing biotite and muscovite granites displaying more evolved compositions (e.g., lower Zr/Hf ratios) indicates that the differentiation sequence reached higher degrees of fractionation at a regional scale. Although crystal fractionation played an important role, late-stage fluid/melt interactions, involving F-rich fluids, imparted specific geochemical characteristics to Macao and SE China highly frac- tionated granitic rocks such as the non-CHARAC (CHArge-and-RAdius-Controlled) behavior of trace ele- ments, leading, for example, to non-chondritic Zr/Hf ratios, Rare Earth Elements (REE) tetrad effects and Nb-Ta enrichment and fractionation. Such process contributed to the late-stage crystallization of accessory phases only found in these highly evolved facies. Among the latter, two populations of garnet were identified in MGI (Macao Group I) highly fractionated granitic rocks: small grossular-poor euhedral grains and large grossular-rich skeletal garnet grains with quartz inclusions. The first group was mainly formed through pre- cipitation from highly evolved Mn-rich slightly peraluminous melts under low-pressure and relatively low temperature (～700 oC) conditions. Assimilation of upper crust metasedimentary materials may have contrib- uted as a source of Mn and Al to the formation of garnet. The second group has a metasomatic origin related to the interaction of magmatic fluids with previously crystallized mineral phases and, possibly, with assimi- lated metasedimentary enclaves or surrounding metasedimentary strata. The highly fractionated granitic rocks in Macao represent the first stage in the development of granite-related W-(Mo)-Sn-Nb-Ta mineraliza- tion associated with coeval more evolved lithotypes in SE China.