Liu Xiaobo (Chinese: 刘晓波; pinyin: Liú Xiǎobō; 28 December 1955 – 13 July 2017) was a Chinese literary critic, human rights activist, philosopher and Nobel Peace Prize laureate who called for political reforms and was involved in campaigns to end Chinese Communist Party one-party rule in China. He was arrested numerous times, and was described as China's most prominent dissident and the country's most famous political prisoner. On 26 June 2017, he was granted medical parole after being diagnosed with liver cancer; he died a few weeks later on 13 July 2017.

Liu rose to fame in 1980s Chinese literary circles with his literary critiques. He eventually became a visiting scholar at several international universities. He returned to China to support the 1989 Tiananmen Square protests and was imprisoned for the first time from 1989 to 1991, again from 1995 to 1996 and yet again from 1996 to 1999 for his involvement on suspicion of inciting subversion of state power. He served as the President of the Independent Chinese PEN Center, from 2003 to 2007. He was also the president of Minzhu Zhongguo  [zh] (Democratic China) magazine starting in the mid-1990s. On 8 December 2008, Liu was detained due to his participation with the Charter 08 manifesto. He was formally arrested on 23 June 2009 on suspicion of "inciting subversion of state power". He was tried on the same charges on 23 December 2009 and sentenced to eleven years' imprisonment and two years' deprivation of political rights on 25 December 2009.

During his fourth prison term, Liu was awarded the 2010 Nobel Peace Prize for "his long and non-violent struggle for fundamental human rights in China." Liu was the first ethnically Chinese person of any citizenship to be awarded the peace prize as well as the first Chinese citizen to be awarded a Nobel Prize of any kind while residing in China. He was the third person to have been awarded the Nobel Peace Prize while in prison or detention, after Germany's Carl von Ossietzky (1935) and Burma's Aung San Suu Kyi (1991).

Liu was born on 28 December 1955 in Changchun, Jilin province, to a family of intellectuals. Liu's father, Liu Ling (刘伶), was born in 1931 in Huaide County, Jilin. A professor of Chinese at Northeast Normal University, he died of liver disease in September 2011. Liu's mother, Zhang Suqin (张素勤; 張素勤), worked in the Northeast Normal University Nursery School. Liu Xiaobo was the third-born in a family of five boys.

In 1969, during the Down to the Countryside Movement, Liu's father took him to Horqin Right Front Banner, Inner Mongolia. His father was a professor who remained loyal to the Communist Party. After finishing middle school in 1974, he was sent to the countryside to work on a farm in Jilin.

In 1977, Liu was admitted to the Department of Chinese Literature at Jilin University, where he founded a poetry group known as "The Innocent Hearts" (赤子心詩社) with six schoolmates. In 1982, he graduated with a BA in literature before being admitted to the Department of Chinese Literature at Beijing Normal University as a research student, where he received an MA in literature in 1984, and started teaching as a lecturer thereafter. That year, he married Tao Li, with whom he had a son named Liu Tao in 1985.

In 1986, Liu started his doctoral study program and published his literary critiques in various magazines. He became renowned as a "dark horse" for his radical opinions and scathing comments on the official doctrines and establishments. Opinions such as these shocked both literary and ideological circles, and his influence on Chinese intellectuals was dubbed the "Liu Xiaobo Shock" or the "Liu Xiaobo Phenomenon". In 1987, his first book, Criticism of the Choice: Dialogs with Li Zehou, was published and became a nonfiction bestseller. It comprehensively criticized the Chinese tradition of Confucianism, and posed a frank challenge to Li Zehou, a rising ideological star who had a strong influence on contemporaneous young intellectuals in China.

In June 1988, Liu received a PhD in literature. His doctoral thesis, Esthetic and Human Freedom, passed the examination unanimously and was published as his second book. That same year he became a lecturer at the same department. He soon became a visiting scholar at several universities, including Columbia University, the University of Oslo, and the University of Hawaii. During the 1989 Tiananmen Square protests, Liu was in the United States but he decided to return to China to join the movement. He was later named one of the "four junzis of Tiananmen Square" for launching a hunger strike in support of the students. He also helped broker a peaceful exit for students remaining in the square. That year also saw the publication of his third book, The Fog of Metaphysics, a comprehensive review of Western philosophy. Soon, all of his works were banned in China.