Optically pumped mid-infrared gas laser is a potential way to achieve high beam quality and high power mid-infrared laser output, showing great development prospective in the future due to its extremely high quantum efficiency, outstanding heat dissipation, great ability for power scaling and extraordinary compactness. The basic principle and history of optically pumped mid-infrared gas laser are introduced, the critical blocks and difficulties in its progress are analyzed, and the expectation of optically pumped mid-infrared gas laser is forecased.