Abstract: The MAEAM model describing the constant ratio of electron density was adjusted, and the phase structure of each component ratio was taken into account based on phase diagrams. Heat of formation of a TiAl alloy was calculated using MAEAM theory. The calculation result yielded change trends consistent with results using the Miedema theory. In order to evaluate the reliability of the proposed calculation method, the heat of formation of NiAl alloys and FeAl alloys was calculated. Calculation results agreed with experimental values and the first principle calculation results.