According to the dipole-dipole approximation of plasmon hybridization theory, the localized surface plasmon resonance (LSPR) spectra of a pair of closely spaced gold and silver nanodisks, i.e. the plasmonic scattering characteristics of the bimetallic nanodisk dimer, have been studied by using the finite element method (FEM). The results show that, the plasmonic scattering intensities of the bimetallic nanodisk dimer are affected by the polarization of incident electromagnetic field and its structure parameters, such as the disk diameter, thickness and gap distance. Moreover, the LSPR spectra of the bimetallic nanodisk dimer have considerably red-shift as the increasing of diameters, the decreasing of thicknesses and gap distance. It is significant to apply the heterodimer plasmonic systems on biological sensors and photosensitive detectors.