The paper uses color infrared remote sensing and field investigation technology to interpret linear structure and fault system in three gorges dam and explains the feature of the fault structure. From these analyses, it concludes that: there are mainly four groups fault in the area, that is : NWW group, SN-NNE group, NW-NWW group and NE-NEE group. NNW group is the best developed among them, NE-NEE group is the second developed, SN-NNE group is the third developed, NW-NWW group is the weakest developed. Through statistic method, the paper counts the linear structures length, quantity, fault cross point numbers in net unit and analyses the regular of the fault distribution in this area and their effect to rock quality and dam base stability. In addition to these, the paper also discusses the environment such as tempreture, pressure when the fault formed and formation history through using the feature of mineral fluid inclusion.