Abstract: A quantitative correlation of physical properties of the surface and subsurface hydrocarbon reservoirs in one oilfield in western China was made in the light of the data on the surface and subsurface capillary pressures.The results of research show that the porosity, permeability,delivery pressure,median saturation pressure,percentage of pore volumes controlled by pore throats,and throat radius tend to decrease under the influence of confined pressures,while the sorting of pore throat tend to be much better.The present study will help improve the precision of reserve calculations and identify the seepage flows in the strata.