He was suspended from the professional tour in January 2023 as part of a match-fixing investigation involving ten Chinese players.

[5][6] Following Zhang's promising performances in the academy and in Chinese tour events, the CBSA awarded him a wildcard for the 2016 International Championship in Daqing.

[10] He competed at the 2018 World Snooker Team Cup representing China with Fan Zhengyi but they lost to India 2–3 in the Round of 16.

At the Scottish Open he produced his best performance to date, beating Chen Feilong, John Astley and Tom Ford to reach the last-16, where he lost to Scott Donaldson.

With wins over Wi Ning, Lin Hui, Fang Xiongman, Ju Reti and Deng Haohui, Zhang successfully progressed from the first event, losing only 4 frames in his six matches.

Zhang Jiankang played for the Sichuan team, alongside Zhou Yuelong and Cai Wei.

In the Q-final Zhang won a tense deciding frame against Cao Yupeng of Suzhou, the tournament favourites.

But ultimately Sichuan lost 4–2 in the final to Shanghai, whose players were Tian Pengfei, Lu Ning and Zhao Jianbo.

However, in the World Championship he beat John Astley 6-4 and Sunny Akani 6-4 (after having led 5–0) before losing to Stephen Maguire 6–3.