Chemical laser is characteristically energized by an exoergic chemical reaction which produces the nece ssary population inversion of lasing species. Based on the enormous chemical energy deposit, several kinds of chemical laser now deliver the cw power outputs of megawatt magnitude, far higher than any other lasers. Accordingiy, along with theimprovem ent of gas medium homogeneity and mode-electivity of the optical cavity, chemical laser has also attained high bearu quality of a near diffraction limited divergence angle. Recent efforts in developing new chemical laser have focused on the short wavelength chemical laser system, e.g. from theearly DF (l=3.8 μm) and HF(λ=2.7 μm) to lateO2(1Δ)-I (λ=1.315 μm) and HF overtone transition laser (～1.35 μm). At present the community of chemical physics are much interested in the visible chemical laser which may be realized by stimulated emission of an electronic excited state.