Abstract: Equation of state(EOS) for iron is developed based on K-primed cold pressure equation and thermal pressure.Thermal pressure consists of three parts,associated with the rigid perfect lattice,harmonic lattice vibrations,and anharmonic contributions,thermal excitation of electrons is also included.In combination with the volume dependence of the Grüneisen parameter and Debye temperature,thermodynamic properties of iron are calculated over a wide range of densities and temperatures relevant to the Earth's core.Detailed results are presented for the temperature,and comparisons are made with available experimental measurements and theoretical predictions.This model will provide the foundation of scientific research about inner core and outer core.