Microhollow cathode discharge (MHCD) is a novel, nonequilibrium, high-pressure, direct current glow discharge. An overview of the research progress on the foundational theory of the MHCD was presented. The excimer radiation from the MHCD is discussed in particular, and then discharge mode (dc discharge, pulse dc discharge, RF discharge) effect to the intensity and the efficiency of excimer radiation is elucidated. The operation way (operation in series, operation in parallel) of the MHCD effect to excimer radiation is also discussed finally.