By analyzing thin sections, scanning electronic microscope and physical properties, the petrology characteristics, pore types and reservoir properties of He 8 member in Gaoqiao area were studied. The result shows that the rocks of the reservoir of He 8 member which deposited in braided delta front are mainly composed of quartz sandstone and lithic quartz sandstone with high compositional maturity and medium textural maturity. The reservoir developed secondary dissolved pores primarily, followed by kaolinite inter-crystalline pores and primary intergranular pores, and a little microcrack. The average porosity is 6.37% and the average permeability is 0.81 mD，and it belongs to typical low porosity and low permeability reservoir. The main factors influencing the reservoir properties were analyzed. The reservoir properties are controlled by provenance and sedimentary facie zone in plane, and controlled by compaction and cementation in the vertical direction, whereas the secondary pores produced by dissolution improve the reservoir properties.