This paper is a case study on the Lower Karamay Formation. By analyzing eight sealed coring wells with small distance and the architecture characteristics of twenty-four wells around, a 3D architecture model of target formation of the study area is built. Different architecture modeling methods practical to fans with different subfacies were derived. Fan head is extensive connecting body mainly composed of sheet-flow sandstone bodies, and the distribution areas of the architecture of different levels are small, so Object-based modeling method is used. The main architecture units of mid-fan are fine sheet-flow grains, braided channel and sheet-flow sandstone body. The braided channel and sheet-flow sandstone bodies have obvious contact belt.