Optically pumped metastable rare-gas laser(OPRGL) have been proposed to overcome the shortcomings of diodepumped alkali-vapor laser in the recent years. The OPRGL promises to realize high-scale output. But how to achieve enough particle density of metastable atoms is still an open problem. Usually, plasma produced by discharge serves as a gain medium of the OPRGL. Here in this paper, we are to reveal the effects of different discharge parameters on the plasma properties, such as particle density of metastab...