Abstract: The Mesozoic A-type granites are widely developed in southeastern China. Spatially, they can be further distinguished into the coastal area zone and the Nanling inland area zone. A-type granites in the coastal area zone were formed mainly in Late Cretaceous （92 - 103 Ma）, while those in the Nanling inland area zone were generated initially in Early Jurassic and lasted till Early Cretaceous （ 186 - 124 Ma）, thus has a long time duration for their formation. Lithologically, A-type granites in the coastal area zone can be further divided into peralkaline and aluminous s ps, while those in the Nanling inland area zone are predominantly of aluminous subgroup. Compared with the A-type granites in the Nanling inland area zone, those in the coastal area zone have more enriched SiO2, Na20 contents, and lower K20, Rb, Sr, Ba concentrations and FeO＊/（FeO＊ ＋MgO） ratios. Nd, Sr isotope tracing indicates that A-type granites in both zones were crystallized from highly evolved magmas, which were originally generated by mixing of crustal materials with variable amounts of mantle components due to different extension degrees in different regions. Integrated investigations on their rock associations and tectonic settings suggest that Atype granites in the coastal area zone were formed in a back-arc extension environment that related to the westward subduction of the Palaeo-Pacific plate beneath the Eurasia plate, while those in the Nanling inland area zone were generated mainly under a within-plate rift setting, which might be jointly constrained by the Tethyan and the Paleopacific tectonic dynamic systems.