An important property of optical metaaterials is the ability to concentrate light into extremely tiny volumes,so as to enhance their interaction with quantum objects.In this work,we numerically study the near-field enhancement and absorption properties inside the cylindrical microcavities formed by a Au-GaAs-Au sandwiched structure.At normal incidence,the obtained reflection spectra show that the resonance wavelength of microcavities operates in the range of 5-5.8 μm.We also calculate the contrast C (C =1-Rmin),which can be increased to 97％ by optimizing the structures geometry parameters.Moreover,we demonstrate that the multilayer structure with sub-wavelength electromagnetic confinement allows 103-10t-fold enhancement of the electromagnetic energy density inside the cavities,which contains the most energy of the incident electromagnetic radiation and has a higher quality factor Q,indicating a narrower linewidth for surface enhanced molecular absorption spectroscopy and the tracking of characteristic molecular vibrational modes in the mid-infrared region.The structure is insensitive to the polarization of the incident wave due to the symmetry of the cylindrical microcavities.The unique properties of the metal-dielectric-metal metamaterials will have potential applications in new plasmonic detectors,bio-sensing and solar cells,etc.