|Died||17 November 2018 (aged 100)|
|Alma mater||Zhejiang University|
University of Edinburgh
|Doctoral advisor||Max Born|
Cheng Kaijia (simplified Chinese: 程开甲; traditional Chinese: 程開甲; pinyin: Chéng Kāijiǎ; 3 August 1918 – 17 November 2018) was a Chinese nuclear physicist and engineer. He was a pioneer and key figure in Chinese nuclear weapon development. He is known as one of the founding fathers of Two Bombs, One Satellite.
Cheng was born in Wujiang, Jiangsu in 1918. He graduated from the Department of Physics of Zhejiang University in 1941. In 1946, he went to the United Kingdom to study at the University of Edinburgh, obtaining a PhD in 1948 under advisor Max Born. He then became a researcher in the UK.
Cheng returned to the People's Republic of China in 1950. He was an associate professor at Zhejiang University, he then went to Nanjing in 1952, where he became an associate professor in Nanjing University, and was later promoted to full professorship.
Cheng was a pioneer of Chinese nuclear technology and played an important role in the development of the first Chinese atomic bomb. He first calculated out the inner temperature and pressure for an atomic bomb blast in China. His calculation was an extremely heavy task and nearly manual, because during that time China did not have any computer or even calculator. He also solved the mechanism of the inner explosion, which could support the design of the bomb. He was the chief director for many nuclear weapon test fields/bases and their explosion processes.
Cheng was elected to the Chinese Academy of Sciences. He was also a standing member of the Science and Technology Committee, Chinese National Nuclear Industry Corporation. He was former vice-president of the Nuclear Weapons Research Institute, and the deputy chief director of the Nuclear Weapons Research Institute, People's Republic of China. 
In 1999, he was awarded "Two Bombs and One Satellite Meritorious Award" for his contribution on atomic bomb and hydrogen bomb. In July 2017, Chairman Xi Jinping awarded Cheng the Order of August First, the highest military award of People's Republic of China.
- Project 596 – China's first nuclear weapons test
- "23位两弹一星元勋已有17人离世 媒体解析其功绩" (in Chinese). china.com. 30 May 2016.
- Kai-Chia, Cheng (1948). "On the theory of superconductivity".
- Chen Kaijia's biography in Baidu.com “我国第一颗原子弹研制的开拓者之一，我国核武器试验事业的创始人之一。在国内第一个计算出原子弹爆炸的弹心温度和压力，其内爆机理研究解决了原子弹的关键问题，为原子弹爆炸威力、弹体结构设计提供了重要依据。……”
- ChinaVitae the biography highlight of Cheng Kaijia
- "景海鹏、程开甲、王刚等10人被授予"八一勋章"". Phoenix News (in Chinese). 28 July 2017.
- "101岁"中国核司令"程开甲逝世：获两弹一星功勋章|两弹一星|程开甲|中科院_新浪军事_新浪网". mil.news.sina.com.cn. Retrieved 17 November 2018.
- ChinaVitae - the biography highlight of Cheng Kaijia
- Holeung Ho Lee Foundation (HHLF) AWARDEE OF TECHNOLOGICAL SCIENCES PRIZE - CHENG KAIJIA (Abstract)
- 两弹一星功勋：核武器专家程开甲院士 Nuclear weapon pioneer - Academician Cheng Kaijia (in Chinese)