In the present work characterization of the heavy end fractions of some Omani light oils has been carried out. To achieve this goal, the necessary thermophysical properties of heavy end fractions of some samples of light oils have been obtained. Thirteen wells from six different fields comprising of northern and central Omani oil fields are studied. Comprehensive detailed pressure volume temperature (PVT) reports that contain three different experiments types have been used in this study. The proposed characterization method is mainly based on the C7+ fraction properties. Comparison between the industry used correlation for splitting the heavy fraction (Katz and Firoozabadi correlation) and the results of thermophysical properties (Tc, Pc, acentric factor, Mw, density and T) of the C7+ fractions was made using PVTsimo software. Different equations of state are examined for obtaining better matching and PR-78 Peneloux was selected due to its good results. The obtained thermophysical properties from PVTsimo are determined after good fitting is achieved between the volumetric properties (Solution Gas Oil Ratio (Rs), formation volume factor (B.), oil density and saturation pressure (Psat) of the oil sample taken experimentally and the values calculated by the most industry used EOS with a very good range of accuracy compared to the available experimental data. Moreover, a general correlation based on the obtained range of critical properties related to a single carbon number is obtained in this work.