China and weapons of mass destruction

The People's Republic of China has possessed nuclear weapons since 1964. It was the last to develop them of the five nuclear-weapon states recognized by the Nuclear Non-Proliferation Treaty (NPT). China acceded to the Biological Weapons Convention (BWC) in 1984, acceded to the NPT in 1992, and ratified the Chemical Weapons Convention (CWC) in 1997.

China tested its first nuclear bomb in 1964 and its first full-scale thermonuclear bomb in 1967. It carried out 45 nuclear tests before signing the Comprehensive Nuclear-Test-Ban Treaty in 1996.

The Federation of American Scientists and the Stockholm International Peace Research Institute estimate China's stockpile at approximately 600 nuclear warheads as of 2025, making it the third-largest in the world. It is the only NPT nuclear-weapon state significantly expanding its arsenal and is projected to reach 1,000 warheads by 2030 and up to 1,500 by 2035. Compared to the arsenals of the United States and Russia, a much smaller proportion of China's warheads are believed to be deployed on their delivery systems, with the remainder stored separately.

Since 2020, the People's Liberation Army has operated a nuclear triad. Of its 600 warheads, it is estimated 376 are assigned to its Rocket Force's Dongfeng intermediate and intercontinental ballistic missiles, 72 to its Navy's Julang-3 submarine-launched ballistic missiles on six Type 094 submarines, and 20 to its Air Force's Jinglei-1 air-launched ballistic missiles for 20 Xi'an H-6N strategic bombers. Approximately 132 warheads await assignment. China is upgrading its triad with the in-development Xi'an H-20 stealth bomber, Type 096 submarine, and large missile silo fields. China fields multiple independently targetable reentry vehicles, and has tested hypersonic glide vehicles and a fractional orbital bombardment system.

In 1964, China adopted a policy of no-first-use (NFU) and called for an international NFU treaty, both of which it continues to advocate. Some of its nuclear forces are reported to have moved toward a launch on warning (LOW) posture in the early 2020s.

China denies currently possessing offensive chemical and biological weapons programs, while the US alleges it is not in compliance with treaty obligations. In its 1997 non-public declaration to the OPCW, China reportedly declared two or three chemical weapon production facilities, now widely believed to be destroyed. Experts suggest this program focused on mustard gas and lewisite.

During the Second Sino-Japanese War, the Imperial Japanese Army's biological warfare department, led by Unit 731, dispersed anthrax, cholera, dysentery, typhoid, plague, and other pathogens, killing between 200,000 and 500,000 people. Japanese forces also used chemical weapons including mustard gas and lewisite, causing an estimated 37,000 to 80,000 casualties. Some 700,000 to 2 million Japanese chemical weapons were abandoned in China, with less than 100,000 recovered as of 2023.