Chenghao-Nanliang area is one of the key blocks of exploration and evaluation in the Longdong oilfield in recent years. It is located in the most favorable oil generation area in the Ordos basin with Chang 6 sand bodies developed. Through the research of petrology, pore type and heterogeneity pattern on the  6 reservoir in the Chenghao Nanliang oilfield, we believe that the divergence of Chenghao Nanliang oilfield’s physical properties and petroliferous poperties is great, and the heterogeneity is strong. Underwater distributary channel deposit sandstones with good porosity and permeability are developed widely in the Chenghao Nanliang area, and are the favorable places for oil and gas accumulation.