The two-dimensional numerical model used is based on solutions of fluid equations in the drift-diffusion approximation for the electron and ion transport coupled with Poisson’s equation for electric field to simulate microcavity discharge qualities. The computation results show the potential profile, electron density distribution, ion density distribution, and electron temperature spatial distribution at the argon pressure of 100 Torr. The potential contour shows that the radial component of the electric field becomes very important as the forming of the cathode sheath. The results indicate the peak electron density is 1020 m-3, and the electron temperature is on the order of several to tens of eV.