Abstract:Rock samples collected from Permian Shangshihezhi Formation (P3sh) and Sunjiagou Formation (P3s) and Triassic Liujiagou Formation (T1l) in the Huigeda hill of Dayu Town in the Henan Jiyuan Basin had been analyzed and studied according to the elements,frequency dependent susceptibility,carbonate and organic matter contents. It was shown that trace and macroelement in the bottom of Jiyuan Fauna fossil stratum in Permian Sunjiagou Formation (P3s) and near P-Tr boundary in the bottom of Triassic Liujiagou Formation (T1l) had changed greatly. Elements Ba,Cr,Hf,Nb,Th,Ti,V,Y,Tl,Zn,Cu,Ga,Pb,Ni,La,Rb,Nd,and K2O, Al2O3,Fe2O3 had high content in the fossil stratum,but elements Zr,W,Sr,Bi,Co,Ce,and SiO2,Na2O had low content,MgO,CaO,Mn kept stable a little. Elements Ba,Hf,Nb,Th,Ti,V,Y,W,K2O,Al2O3,SiO2,Na2O,Bi,Fe2O3,Ni,Co,La,Nd,Ce and organic matter content had increased obviously from the Triassic bottom,but elements Cu,Ga,Pb,Tl,Zn,Cr,Zr,Sr,MgO,CaO,and frequency dependent susceptibility,carbonate content decreased greatly. This P-Tr section not only recorded the end-Permian mass extinction,but also had an obvious P-Tr boundary. It is shown that event and boundary formation had a closed-correlation with deposition environments and palaeoclimate at that time. The directive reason to form event and boundary were the shallow water and warm climate and high chemical weathering. The sediment face was the river-delta environment with warm and wet during the Shangshihezhi Formation (P3sh). And delta plain face during Sunjiagou Formation (P3s),had very strong weathering and extremely hot and rainy at the early and end periods. But water level in this basin rose a little to make sandy sediments forming in the front of delta. Waterbody had continued to expend during Triassic Liujiagou Formation (T1l) with a relatively falling temperature.