The Beishan area is located at the southern end of the middle section of the Central Asian Orogenic Belt (CAOB). The widely exposed marine Permian in this area is one of the youngest marine deposits in the CAOB. It is an ideal carrier for analyzing the late evolution of the Paleo- Asian Ocean (PAO). However, the paleogeographic discussion of the PAO is hindered by the unbalanced distribution of the provenance data and the lack of statistical analysis. This study reports 681 U- Pb ages and 192 Hf isotopic data from eight sections from the central and southern Beishan regions. The paleogeographic pattern is reconstructed based on isochronous stratigraphic correlation and statistical analysis of published samples of detrital zircons from the Lower- Middle Permian strata. During the Early- Middle Permian, the southward subduction of the Hongshishan ocean resulted in the Heiyingshan arc and a back- arc rifting basin. The deposits on the northern margin of this rifting basin were fed from the Precambrian basement (926~775 Ma) and Ordovician- Silurian plutons (485~421 Ma) in the Hanshan Block. The sediments on the southern margin were sourced from the Mazongshan Uplift. This uplift composed of the Ordovician- Devonian plutons (470~367 Ma) was caused by the closure of the Hongliuhe- Xichangjing ocean in the early Paleozoic. The realm of this uplift covers the main areas of the Mazongshan arc and northern Shuangyingshan block. Detritus of the southern and northern margins of the Liuyuan rifting basin were respectively sourced from Carboniferous- Permian volcanic rocks (322~270 Ma) and early Paleozoic plutons of the Mazongshan Uplift. The detrital exchange occurred in the depocenter of the Liuyuan basin. The paleogeographic reconstruction indicates that the Hongshishan ocean as the main branch of the PAO lasted in the Early- Middle Permian and several rifting basins developed in the back arc regions.