Abstract: The Shishuyuan Formation distributed in the Nanzhao area,Henan,is represented by alow-grade metarnorphic clastic sequence. The discovery of abundant Late Paleozoic fossils（e.g.Calamospora cf. microrugosa, Dictyotriletes minor, and Punctotiporites minutus ） in the limestoneinterbds in its lower and middle oarts has demonstrated that this formation should be Late Pa-leozoic in age. From its prctoliths and their deformation and metamorphism,it should not be as-signed to the Erlangping Group （ Lower Paleozoic ） or the Kuanping Group（upperProterozoic）.Stratigraphically it is largely equivalent to the Nanwan Forrnation cf;he XinyangGroup and the Fenbigou Formation on the Henan-Shanxi Border. in the Late Paleozoic,NorthQinling was a sea trough,overlain unconformably by Late Triassic continental coal measures.This indicates that this trough closed at the end of the Permian. Then the North QinlingVariscan fold belt was formed.