[8][9] Han studied English literature at Soochow University after graduating from the Republic of China Military Academy, and earned a Master of Arts (M.A.)

[10][11][12] His master's degree thesis was titled, "A Look at the Negotiations during the 'Two Airlines Uprising' from the Perspective of the Communist Party of China's (United Front) Strategy" (Chinese: 從中共「對臺統戰」策略看兩航談判).

[15] Han won the Zhonghe seat on the Taipei County Council in 1990, and served until 1993, when he took office as a member of the Legislative Yuan.

[19] For their support of the construction of the Lungmen Nuclear Power Plant, Han, Hung Hsiu-chu, Chan Yu-jen [zh], and Lin Chih-chia were targeted with an unsuccessful recall referendum.

[36] Han defeated Chen Chi-mai in local elections held on 24 November 2018, and became the first mayor of Kaohsiung affiliated with the Kuomintang since Wu Den-yih left office in 1998.

[39] In addition, he sought fluent English speakers to fill vacancies in his administration pertaining to promotion and public relations.

[43] On 24 February 2019, Han began a five-day trip to Malaysia and Singapore to discuss business and tourism opportunities for Kaohsiung, his first official overseas visit as mayor.

[44] In March 2019, Han and a delegation of municipal officials visited Hong Kong, Macau and Mainland China for a seven-day trip to discuss agriculture.

Members of the delegation included Han and his wife, deputy mayor Yeh Kuang-shih, and ten Kaohsiung City Councilors.

He met with Congresspeople Ted Lieu and Judy Chu and also Los Angeles Deputy Mayor Nina Hachigian.

[66][67] A week after that statement, Han said that he would abide by Kuomintang's primary process, opening the door for his potential nomination as a presidential candidate.

[75][76] Han held a presidential election rally on 8 September 2019 at Xingfu Shuiyang Park (Chinese:幸福水漾公園) in Sanchong District, New Taipei,[72] with former president Ma Ying-jeou and KMT chairperson Wu Den-yih in attendance.

Han conveyed four main points of his campaign platform, which were to defend the Republic of China, to love Chinese culture, to uphold freedom and democracy and to never forget the struggling people.

[77] He began a three-month leave of absence despite having serving only six months of his term to focus on his presidential campaign, delegating mayoral duties to Yeh Kuang-shih from 15 October 2019.

[81][82] Han and Chang finished second in the presidential election to incumbent president Tsai Ing-wen and her running mate William Lai.

[89] Following his recall as Kaohsiung mayor, he appeared at a meet-and-greet announce his appointment as president of the Dianliang Foundation and to promote his new book, which aims to improve bilingual education in elementary schools and provide support to elderly citizens.

On 16 November 1990, during then-Taipei County magistrate You Ching's presentation, Han threw a thermos at You then ran toward the podium and attempted to choke him.

[95] Days leading up to the 2020 election to recall Han as Kaohsiung mayor, National Police Agency director-general Chen Chia-chin stated that there were rumors that gang members were expected to be at voting stations to intimidate and suppress voters.

However, Chen, in a separate press conference, noted that the alleged involvement with organized crime was not substantiated by evidence and was a rumor.

[97] No evidence suggesting Han's involvement were reported following the recall; some sources criticized DPP's abuse of executive powers in its attempt to obstruct the voting process.