The Surface-Area-Difference (SAD) model has been generalized to account for the cohesive energy of nanoparticles with different compositions (NDC) in different shape, where the particle shape is described by the shape factor. It is found that the cohesive energy of NDC depends on the particle size, the particle shape and the atomic percent of each composition, which can be simply regarded as mathematical mean values of the cohesive energies of all the compositions.