His father Zhang Weihua (张卫华) played football in the Chinese Jia-A League as a defender for Shanghai Shenhua.

At the 2012 Shanghai Rolex Masters, Zhang – only sixteen at the time – was given a wild card entry into the qualifying draw; he lost to world number sixty one Brian Baker, winning just three games in his debut clash with a top one hundred ATP player.

After a six month hiatus from professional events, Zhang made his 2013 ITF Men's Circuit debut in May at the USA F12 challenger, where Greg Ouellette got the better of the youngster in three sets.

Zhang would skip half of the 2014 ITF Men's Circuit, finishing the year with only thirteen participations in senior-level events, including a quarterfinal showing at a Futures tournament in Cyprus.

March brought Zhang his first victories of 2015, where he bested Jan Zieliński and top-400 player Bastian Trinker in Turkey's 11th Futures event of the year.

French tournaments continued being the bearers of good results for Zhang, as he followed his Futures title with a second final three weeks later, this time in Bourg-en-Bresse.

Zhang inexplicably missed the first four months of the 2016 ATP World Tour, and when he did arrive, he returned on the 2016 ITF Men's Circuit.

Zhang's ranking hovered 800 from September, 2016, to May 2017, when the Chinese youngster, still only twenty years old, reached a third Futures final, this time in Lu'an, China.

[13][14] On the 26th of November, 2017, after defeating Te Rigele in a three-set final, Zhang won the China Tennis Grand Prix Cup title for the first time.

He won the 2019 Jinan International Open, beating top one-hundred player Soonwoo Kwon en route.

He also reached the second round of both the 2019 Zhuhai Championships and the 2019 China Open, with the latter being a loss to top-five player and eventual champion Dominic Thiem.

Zhang concluded October with a second Challenger crown, ousting Li Zhe in the final round of the 2019 Shenzhen Longhua Open.

He played and lost in the first round of the 2020 Tata Open Maharashtra, and failed to progress past qualifying at the 2020 Dubai Tennis Championships.

Having lost early or in qualifying for many previous events on the 2022 ATP Challenger Tour, Zhang finally managed to progress beyond the second round at a tournament for the first time in almost a year.

The following week in Florida, at the 2022 Tallahassee Tennis Challenger, Zhang made it to the last four, losing to Wu Tung-lin in two close sets.

Zhang then made a Challenger quarterfinal for the third week in a row, losing to former top-ten player and 2017 Rolex Paris Masters champion Jack Sock in the final eight.

Zhang failed to reach the Wimbledon Championships' main draw again, losing in the second round of qualifying to Daniel Masur.

He reached the final without dropping a set, eliminating both third-seeded Manuel Guinard and seventh-seeded Pablo Cuevas en route.

[21] He made his debut at the US Open, qualifying for the main draw alongside his friend Yibing Wu, making history for his country.

After qualifying for Naples, Zhang beat Márton Fucsovics and sixth seed Sebastián Báez in straight sets to reach his first ATP Tour-level quarterfinal for the season and first since 2017.

He then defeated 21st seed Denis Shapovalov for his first top 30 win, to reach the third round of a Masters for the first time in his career.

[31] He saved three match points in his first top 10 win over eight seed Taylor Fritz to become the first Chinese man in history to reach the quarterfinals at a Masters tournament.

[35] Next he defeated qualifier Thiago Agustín Tirante to reach the third round of this Major for the first time since Kho Sin-Kie in 1937.

In Eastbourne, he defeated Lorenzo Sonego in the first round, then Maxime Cressy in a thrilling three set match to advance to the quarterfinals, bringing him up to a career high ranking of No.

52, becoming the highest ever ranked male Chinese tennis player and from any other East Asian country, passing Wu Yibing's record of No.

In Hamburg, he reached the quarterfinals of an ATP 500 for the first time in his career defeating Jan Choinski and upsetting World No.

At the US Open he reached the third round defeating JJ Wolf[37] and fifth seed Casper Ruud in five sets and becoming the first Chinese man to beat a top-5 player.

[40] He made his debut at the 2024 United Cup as the top ATP player of team China and the highest ranked man from an East Asian country in history.

In doubles, on his debut, he reached the quarterfinals with Tomáš Macháč taking out the 2020 champions and third seeds, Rajeev Ram and Joe Salisbury.

[51] At the 2024 Hangzhou Open, he reached his third and a historic all-Chinese semifinal with compatriot Bu Yunchaokete, following wins over Denis Yevseyev, Mattia Bellucci and Roberto Carballés Baena.