Deng Hanwen started his football career when he joined
Guizhou Renhe's youth academy in 2009. He was then loaned out to
Alverca and
Real Massamá for youth training as part of the
Chinese Football Association's 500.com Stars Project between 2011 and 2013. He returned to China in 2013 for the
2013 National Games of China. Deng transferred to
China League Two side
Taiyuan Zhongyou in the 2014 season. On 27 September 2014, he scored his first senior goal in a 1–1 away draw against
Lijiang Jiayunhao in the
2014 China League Two play-offs. He scored one goal in 15 appearances as the club finished as runners-up and was promoted to the second tier, where the club changed its name to
Nei Mongol Zhongyou. On 7 May 2016, he scored his first goal in the
China League One in a 3–2 home win against
Meizhou Hakka. After his promising performances in the 2016 season, Deng became the first national team player in club history when he was called up to the
Chinese national team in December 2016. He made his debut for the club on 11 March 2017 in a 2–2 home draw against
Shanghai Shenxin. On 8 October 2017, he scored his first goal for the club in a 2–0 home win against
Xinjiang Tianshan Leopard, sealing the club's promotion back to the top tier. During the 2017 season, Deng made 25 appearances and scored once in all competitions. On 24 December 2017, Deng transferred to
Chinese Super League side
Guangzhou Evergrande. He made his debut for the club on 26 February 2018 in a 4–1 win against
Shanghai Shenhua in the
2018 Chinese FA Super Cup. On 2 March 2018, he made his Super League debut in a 5–4 home loss against
Guangzhou R&F. On 2 May 2018, in the fifth round of
2018 Chinese FA Cup against
Guizhou Hengfeng, Deng failed to convert his kick in the penalty shootout, having his shot saved by
Su Boyang as Guangzhou lost 4–1 in the penalty shootout. On 29 July 2018, Deng scored his first goal for the club in a 5–0 home win against Chongqing Lifan. On 29 April 2022, he signed with newly promoted top tier side
Wuhan Three Towns. He would go on to make his debut on 3 June 2022, in a league game against
Hebei FC, which ended in a 4-0 victory. After the game he would go on to establish himself as a regular within the team that won the
2022 Chinese Super League title.On 5 December 2025, Deng updated his social media, formally bidding farewell to the club that he has played for over the past four years. On 5 January 2026, Deng joined
Yunnan Yukun. ==International career==