By the end of 2019，443 units were in operation worldwide，with a total installed capacity of over 392 gigawatts. There are 54 nuclear power units under construction in the world with a total installed capacity of 57.4 gigawatts. At present，major nuclear power countries in the world are continuously investing in the research and development of the third generation nuclear power technology，small modular reactors，advanced nuclear reactor types，fusion reactors，etc. The supply capacity of the first stage of the world nuclear fuel cycle is generally surplus. Forecast data from major energy/nuclear power institutions in the world show that the installed capacity of nuclear power in the world will increase significantly in the future，and the installed capacity of nuclear power will increase by 60%-146% by 2050.