The shape and size dependent melting thermodynamics of metallic nanoparticles are predicted by application of bond theory model, free of any adjustable parameter. Thermodynamic properties like Debye frequency, Curie temperature, melting entropy and enthalpy of Al, Sn, In, Cu, β-Fe and Fe3O4 for spherical and non spherical shapes nanoparticles with different size have been studied. In this model, the effects of relaxation factor for the low dimension solids are considered. The depression in Debye frequency, Curie temperature, melting entropy and enthalpy is predicted. The model predictions are supported by the available experimental and simulation results.