As of July 2026^[update], 63 nuclear power units are operational in mainland China, second globally to the United States, which has 94. The installed net power is 62.331 GW of electricity, third after US's 96.9 GW, and France's 63.0 GW. Nuclear power generates per year 450 TWh of electricity, ranked second globally), which is 4.82% of the 2025 nation's total energy production in China. There are over 38 further units under construction with a total power of 36.2 GW, ranked first for the 19th consecutive year.

Nuclear power has been looked into as an alternative to coal due to increasing concerns about air quality, climate change and fossil fuel shortages. China aims to generate 200 GW by 2035, produced by 150 additional reactors, at a cost of US$440 billion. China has two major nuclear power companies, the China National Nuclear Corporation operating mainly in northeast China, and the China General Nuclear Power Group operating mainly in southeast China.

China aims to maximize self-reliance on nuclear reactor technology manufacturing and design, although international cooperation and technology transfer are also encouraged. Advanced pressurized water reactors (PWR) such as the Hualong One, CAP-1000, CAP-1400 are the mainstream technology in the near future, and the Hualong One is also exported to Pakistan and will be exported to Kazakhstan. China plans to build as many as thirty nuclear power reactors in countries involved in the Belt and Road Initiative by 2030.

By 2050, fast neutron reactors are planned as the primary reactor type, with a planned 1400 GW capacity by 2100, and two CFR-600 units would be ready in 2026. China was also the first country to operate a Generation IV reactor, the HTR-PM at Shidaowan in Shandong, a pebble-bed type high-temperature gas-cooled reactor. It was connected to the grid in December 2023, becoming the world's first Generation IV reactor to enter commercial operation. China's Thorium Molten Salt Reactor project aims to utilize the thorium fuel cycle, including the TMSR-LF1 prototype operational since 2023. China is involved in the development of nuclear fusion reactors through its participation in the ITER project. It also conducts domestic research through facilities such as the EAST Tokamak in Hefei, as well as advance experimental projects including the Burning Plasma Experimental Superconducting Tokamak and the CFETR, which aim to develop DEMO-class reactors with power output exceeding >1 GW.

Nuclear research in China began during the 1950s, centered at the Institute of Atomic Energy, with assistance from the Soviet Union, and primarily to develop China's nuclear weapons. Following China's reform and opening up, the military nuclear industry shifted towards civilian power, with the first nuclear power plant, Qinshan-1, connecting to the grid in 1991. In the 21st century, China imported many gigawatt-class PWR reactor designs: the French EPR, Russian VVER-1000, and US AP1000.

In the Cold War, Beijing's initial motivation for developing nuclear power was largely driven by security concerns. Between 1950 and 1958, Chinese nuclear power construction heavily relied on cooperation with the USSR. The first initiative was launched with the establishment of the China-Soviet Union Nonferrous Metals and Rare Metals Corporation and the first central atomic research facility, the Institute of Atomic Energy of the Chinese Academy of Sciences in Beijing. In February 1955, a chemical separation plant for the production of weapons-grade U-235 and plutonium was created with Soviet aid in Xinjiang and in April the Changchun Institute of Atomic Energy was established. Several months later, on 29 April 1955, the Sino-Soviet Atomic Cooperation Treaty was signed. The China National Nuclear Corporation (CNNC) was also established in 1955. In addition to cooperation with the USSR, China began to learn nuclear technology by sending students to the USSR. In December 1958, nuclear power development had become the top priority project in the Draft Twelve Year Plan for Development of Science and Technology.

The second phase was characterized by the goal of being completely self-sufficient in nuclear power development. In June 1959, the USSR officially ended any forms of nuclear aid to China, withdrawing Soviet technicians. China suffered but continued nuclear power development through massive research and input. In order to rapidly strengthen its atomic energy industry, the Central Committee decided that China must dedicate further resources exclusively to nuclear-related activities. Consequently, the Institute of Atomic Energy created branch institutes of research organizations in every province, major city, and autonomous region. By the end of 1963, China had built more than forty chemical separation plants for the extraction of uranium and thorium. In the year between 1961 and 1962, China accomplished significant achievements in nuclear development which consolidated future applications. From 1959 to 1963, a gaseous diffusion plant utilizing a large 300 MW reactor was under construction at Lanzhou. It was estimated that the Chinese invested over $1.5 billion in the construction of this plant.

After the explosive progress in the 1950s, Chinese nuclear development slowed down, possibly because of the Cultural Revolution, so only one nuclear test took place in 1970. On 8 February 1970, China issued its first nuclear power plan, and the 728 Institute (now known as Shanghai Nuclear Engineering Research and Design Institute) was established.