One of the important issues in reservoir engineering is the recognition of the heterogeneity of oil reservoirs which has a major effect on reservoir recovery and expolation. Capillary pressure is one of the important parameters controlling the movement of fluids in oil reservoirs. The heterogeneity of capillary pressure means that the values of this parameter vary in different areas of the reservoir. Typically core samples are taken around the wells and thease cores are analyzed and tested in laboratories and their various properties are measured. Thus the fundamental question of this project is "how to use the measured properties in laboratory to introduce the entire reservoir properties?" For this purpose various methods have been proposed to homogenize (scaling up) capillary pressure curves. The methodology is that hererogeneous models are made of different rock types at first. Then using history matching process, the actual capillary pressure curve is obtained for reservoir block. In the following different homogenization (scaling up) methods are applied on reservoir block model, and homogeneous capillary pressure curve is obtained for each model. By comparing the capillary pressure obtained from homogenization methods and the capillary pressure obtained from history matching (actual capillary pressure curve), the validity of each homogenization methods are determinded. In this project four new methods are proposed for homogenization of caoillary pressure curve. Thease methods are "J-function method", "Pore size distribution method", "Skjaeveland curve fitting method" and "The Proposed method". Finally by analyzing and validating each method the error rate of each method is reported to be 8%, 7.3%, 9.8% and 1.2% respectively. So the proposed homogenization method is approved as a precise and reliable method for homogenization (scaling up) of capillary pressure curves.