A novel model for light propagation in elliptical-hole photonic crystal fibers (PCFs) is developed in terms of orthogonal function model. A new method for constructing supercell lattice is proposed; with this method the transverse index profile is decomposed into two periodic structures, and the mode field is decomposed using Hermite-Gaussian functions. The propagation constant and the mode field distribution of the PCF can be calculated by recasting the Maxwell equations into on eigenvalue system. With this model, the mode properties including dispersion properties, polarization properties and mode area can be analyzed for circular or elliptical hole PCF.