The tectonic settings of the southern Central Asia Orogenic Belt (CAOB) in the late Paleozoic to early Mesozoic have long been controversial. The study carried out an investigation for granodiorite and biotite adamellite in Hanwula of Xiwu Banner，Inner Mongolia using petrology, zircon U- Pb isotopic geochronology and geochemistry. LA- ICP- MS U- Pb dating yields two crystallization ages of about 253. 8±1. 2 Ma and 240. 5±0. 78 Ma for the granodiorite and two ages of 249. 6±1. 7 Ma and 240. 4±0. 59 Ma for biotite adamellite, representing the tectonic- magmatic event in the late Late Permian to Early- Middle Triassic. Petrological and geochemical study indicates that the granodiorite has the aluminum saturation index (A/CNK) of 0. 89 to 1. 13, suggesting that it belong to calk- alkaline I- type granite. Geochemical analysis shows that the rock has SiO2 of 65. 97%~70. 56%(＞56%），MgO of 1. 33%~1. 70%（＜3%），Al 2O 3 of 14. 75%~15. 01%（≈15%）, high Sr of 483. 2×10 -6 ~541. 9×10 -6 (＞400×10 -6 ), low Y of 10. 46×10 -6 ~13. 35×10 -6 , (＜18×10 -6 ), and Yb of 0. 77×10 -6 ~1. 45×10 -6 (＜1. 9×10 -6 ). Distinct fractionation between LREE and HREE and (La/Yb) N varying between 12. 07~33. 05, along with unapparent negative Eu anomaly ( δ Eu=0. 78~0. 89) in the chondrite- normalized REE pattern, all suggest that the granodiorite belong to adakite. The biotite adamellite has an A/CNK of 1. 05~1. 20, suggesting that it belongs to peraluminous and high- K calc- alkaline series. The rock is characterized by high silicon (SiO 2=72. 73%~77. 02%), high alkali (K 2O+Na 2O=7. 36%~8. 47%), low P 2O 5 (0. 016%~0. 085%) and CaO (0. 38%~1. 67%), enrichment of Th, U, K, Nd, Hf, and depletion of Ba, Nb, Ta, P, T and HREE, significant negative Eu anomalies ( δ Eu=0. 08~0. 61), and high degree of differentiation (DI=85. 78~95. 76). P 2O 5 is negatively correlated with SiO 2 while Y is positively correlated with Rb, indicating that biotite adamellite belongs to highly fractional I- type granite. Lithogeochemical characteristics above indicate that the Hanwula granites were probably the product of different batches of emplacement of crystallization/differentiation of magmas formed by partial melting of the thickened crust at different depths. Combined with petrological and geological features of the rocks, it can be concluded that the granites of the Late Permian to Early- Middle Triassic were most probably formed in the tectonic setting of collision, which was magmatic response to collision between the Siberian plate and North China plate after closure of the Paleo- Asian Ocean in the Late Permian.