Abstract: This paper put forward a ICT (Industrial Computerized Tomography) measuring way of density difference which mea-sures the porosity distribution of reservoir core for the further studying of porous structure and the porosity distribution using technology of ICT, and the measuring way have been applied to measure the porosity and porosity distribution of a core sample
from certain oilfield. The result indicates that the CT density difference method is effective to measure the porosity distribu-tion. The method is faster and more accurate than conventional methods, and it has also the merit, such as no damage to core sample and similar to formation condition. Therefore, it is an advanced method for measuring the rocks properties and follow-
ing the tracks of formation fluid.

Key words: industry computerized tomography (ICT), porosity distribution, density difference