Chen Chien-jen OS KSG KHS is a Taiwanese epidemiologist and politician who has served as the premier of the Republic of China (Taiwan) since 2023. He joined the Chen Shui-bian presidential administration in 2003 as leader of the Department of Health, serving through 2005. He later headed the National Science Council between 2006 and 2008. Chen then served as a vice president of Academia Sinica from 2011 to 2015. Later that year, Chen joined Tsai Ing-wen on the Democratic Progressive Party presidential ticket and served as Vice President of Taiwan from 2016 to 2020. Chen joined the DPP in 2022 and was appointed premier in January 2023.

The premier of the Republic of China, officially the president of the Executive Yuan, is the head of the government of the Republic of China of Taiwan and leader of the Executive Yuan. The premier is nominally the principal advisor to the president of the republic and positioned as the head of central government.