The luminous efficiency improvement is a key issue for making a plasma display into a large flat panel device. We suggest a new combination of a three-component gas, Ne-Xe-Ar, to achieve a high luminous efficiency of a color plasma display panel. The densities of 26 species and the electron temperature were calculated by zero-dimensional simulation, and we compared the results of zero-dimensional simulation with a measurement of vacuum ultraviolet (VUV) intensity covering a 140-180 nm wavelength range, in order to find the optimum mixing condition of Ne-Xe-Ar gas in a color plasma display panel. Reaction mechanism was analyzed by a computational work to comprehend the mechanism of discharge in Ne-Xe-Ar as well as Ne-Xe. The maximum peak point of the Xe*(S-1(4)) state was obtained in 0.5% of Ar mixing ratio by simulation and the maximum luminous efficiency was measured at the same point of 0.5% Ar mixing ratio in VUV measurement. The luminous efficiency has been improved considerably (about 30%) with a 0.5% Ar addition, compared with the Ne-4% Xe mixing gas.