Chen Chien-jen

Chen Chien-jen OS KSG KHS (, born 6 June 1951) is a Taiwanese epidemiologist and politician who has served as the premier of the Republic of China (Taiwan) since 2023.

Chen Chien-jen was born at his family home in Cishan, Kaohsiung County, in 1951, as one of eight children.

His father, Chen Hsin-an, served as Kaohsiung County Magistrate from 1954 to 1957.

Chen's mother Chen Wei Lien-chih managed a daycare.

Chen is married to Lo Fong-ping, whose family is from Nanjing.

Chen Chien-jen is a devout Catholic.

Chen and his wife were invited to visit the Vatican several times by popes John Paul II, Benedict XVI, and Francis.

Chen obtained a master's degree in public health from the National Taiwan University, and received his Sc.D in human genetics and epidemiology from Johns Hopkins University in 1977 and 1982, respectively.

He began his medical career by researching hepatitis B, and helped raise awareness about vaccination for the disease in Taiwan.

Chen further researched on the liver cancer risk of people with hepatitis B. Chen also discovered a link from arsenic to blackfoot disease.

The arsenic research lead to the revision of international health standards for arsenic exposure.

He joined the Chen Shui-bian presidential administration in 2003 as leader of the Department of Health, serving through 2005.

Chen served as Minister of Health from 2003 to 2005.

As health minister, he was praised for effectively managing the SARS epidemic through quarantine and screening procedures, despite Taiwan's non-membership in the World Health Organization complicating the coordination of research efforts.

His successor Hou Sheng-mao credited Chen with reforming the National Health Insurance program.

He later headed the National Science Council between 2006 and 2008.

Chen led the National Science Council from 2006 to 2008.

He has been invested as a Knight of the Equestrian of the Holy Sepulchre of Jerusalem (2010) and a Knight of the Pontifical Equestrian Order of St. Gregory the Great (2013).

He served on the board of trustees of Fu Jen Catholic University.

Chen then served as a vice president of Academia Sinica from 2011 to 2015.

Between 2011 and November 2015, Chen was a vice president of Academia Sinica.

On 16 November 2015, Chen was confirmed as the running mate for Tsai Ing-wen in the 2016 Taiwanese presidential election after media speculation earlier in the month.

During the campaign, Chen became known by the nickname Brother Da-jen (大仁哥), after a character portrayed by Chen Bolin on the romantic drama In Time with You.

Chen is the first Catholic vice presidential nominee in Taiwan.

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.

He was a member of the Board of Trustees of Fu Jen Catholic University before running for the presidential election and served as Fu Jen's Robert J. Ronald Chair Professor after leaving office.

On 16 January 2016, Tsai and Chen won the presidential election in a landslide.

Chen took up his post as Vice President on 20 May 2016.

In March 2019, Chen announced that he would not seek a second term as vice president alongside Tsai.

Chen received international attention for his role in leading Taiwan's response to the COVID-19 pandemic due to his unique position as both vice president and his epidemiologist background.

Days before he stepped down from the vice presidency, Chen stated that he would return to the Academia Sinica as a research fellow and thus forgo the pension connected to his political office.

On May 17, 2019, the Legislative Yuan approved the same-sex marriage bill, Chen supported it by writing "The Executive Yuan has courageously assumed its responsibility, exercised its utmost wisdom and patience, and continuously communicated and coordinated with the pro and con sides in an effort to reduce social disagreements, proposing a bill that is consistent with the conclusion of the Justice's interpretation of the Constitution and responsive to the majority opinion of the referendum. In the face of the tensions between the pro and con sides, the legislators still uphold the democratic spirit of accommodating diverse opinions and complete the legislative work of the bill smoothly".

In December 2021, Chen applied to join the Democratic Progressive Party, and formally became a member in February 2022.

In January 2023, he rejoined the Tsai administration as premier of Taiwan, taking office on 31 January.

Chen and the members of his cabinet submitted their joint resignations on 18 January 2024.