The pyrochemical process in molten salts for spent nuclear fuel reprocessing and radioactive waste treatment has been developed since 1988. The pyrochemical process for metallic fuel reprocessing has been started using electrorefining. The electrowinning for spent oxide fuel in molten salts has been developed since 1994. The radioactive waste treatment such as metallic waste contaminated by uranium and chemical trap materials in uranium enrich plant, zirconium recycle for spent zircaloy waste from Light Water Reactors was based on the spent nuclear fuel reprocessing. A treatment process for fuel debris in Fukushima Daiichi Nuclear Power Plant recently has been developing. This paper reviews pyrochemical process for spent nuclear fuel reprocessing and radioactive waste treatment.