Abstract:The study and discussion of petrology and geochemistry have revealed that there exists two kinds of A-type granites in Tongbai-Dabie orogenic belt: peralkaline and aluminous granites.The peralkaline A-type granites include alkaline feldspar granite and quartz syenites, characterized by ACNK=0.72~0.97 and NKA=1.02. The aluminous A-type granites also include alkaline feldspar granite and quartz syenites, characterized by SiO2=67.73%~77.60%, rich alkali, Na2O+K2O=7.97%~9.60%, ACNK=0.72~1.03, NKA=0.84~0.97, rich REE,δEu=0.12~0.57 and rich Zr, Nb, Ga and Y. Compared with high fractionated I_type granites, the high Si(SiO2>72%) aluminous A-type granites show rich Fe (FeOT>1.50%),high Zr+Nb+Ce+Y and Ga/Al as well as high zircon saturation temperature (845~880℃).The A-type granites were formed in a post-orogenic environment. It is suggested that Tongbai-Dabie orogenic belt entered the phase of extension and collapse in Late Cretaceous, during which the orogenic movement ended.