The existed theories and methods for calculating interfacial thermal conductance of solid-solid interface lead to diverse values that deviate from experimental measurements. In this letter, We propose a model to estimate the ITC at high temperature without comprehensive calculations, where the interface between two dissimilar solids can be treated as an amorphous thin layer and the coordination number density across interface becomes a key parameter. Our model predicts that the ITCs of various interfaces at 300K are in a narrow range: 10$^{7}$W m$^{-2}$K$^{-1}$ $sim $10$^{9}$ W m$^{-2}$ K$^{-1}$, which is in good agreement with the experimental measurement.