Early career Cao was selected as a wild card for the
China Open twice, losing to
Stuart Pettman in
2009 and
Kurt Maflin in
2011. In April 2011, he beat
Hossein Vafaei 7–3 in the final of the
Asian Under-21 Championship, and in doing so earned a place on the main professional snooker tour for the
2011–12 season.
First season as a professional Cao qualified for the
2012 World Snooker Championship in his debut season after defeating
Kurt Maflin 10–2,
Dave Harold 10–9 (coming back from 6–9 down),
Nigel Bond 10–7 and
Tom Ford 10–9 in the qualifying rounds. At the venue stage he put in an outstanding performance beating
Mark Allen (world number 11) 10–6 to reach the last 16. After the match, Allen accused Cao of dishonesty following what he perceived as a foul shot which Cao did not own up to when he was leading 5–4. Allen also said that "blatant cheating" might be "a bit of a trait for the Chinese players". Television replays of the incident proved inconclusive; Cao stated that he did not remember the shot, for he was focusing on the game. Cao finished the season ranked world number 70, outside of the top 64 who retain their places on the snooker tour. However, he was awarded the second nomination from the Chinese national governing body for a spot in the
2012–13 season.
2012/2013 season Cao qualified for the second ranking event of the season, the
Australian Goldfields Open, by beating
Paul Davison,
Alfie Burden and
Mike Dunn all by 5–2 scorelines. He received a bye in the final qualifying round due to
Anthony Hamilton's withdrawal, and then came through a wild-card match against Johl Younger once in Australia to reach the last 32. Cao was beaten 5–4 by
Martin Gould in the second round, without there ever being more than a frame between the players. He made a 143 break in the sixth frame, the highest of his career to date. A month later, Cao won three qualifying matches to reach the
International Championship, played in
Chengdu, in his homeland. It was Allen who triumphed this time, with a 6–2 win. He also came through three matches to qualify for the
UK Championship for the first time. Cao could only win one more match during the rest of the season, culminating in the second round of
World Championship Qualifying where he lost 10–7 to
Zhang Anda, meaning he was unable to repeat last year's run to
The Crucible. He was ranked world number 66 in the end of season rankings.
2013/2014 season Cao reached the first quarter-final of his career at the
2013 Wuxi Classic, the opening ranking event of the
2013–14 season. He qualified by defeating
Paul Davison 5–1 and then saw off
Michael White 5–3, world number eight
Barry Hawkins 5–4 and
Ben Woollaston 5–3. He faced world number one,
Neil Robertson and, although he led 4–3 and made five breaks above 50 in five separate frames during the match, he was edged out 5–4. This was the closest match Robertson had and he ultimately went on to win the title. Cao won the first title of his career in winning the gold medal in the men's singles at the
Asian Indoor and Martial Arts Games by beating
Ding Junhui 4–2 in the final. Cao qualified for four more ranking events during the season but lost in the first round in each one, coming closest to progressing at the
International Championship when he came back from 5–2 down against Ding to level before losing the final frame. All 128 players on the snooker tour earned automatic entry into the first round of the
Welsh Open with Cao seeing off
David Grace 4–2, but then lost another deciding frame in the next round this time against world number five, Hawkins. Cao's world ranking went up 20 places during the season as finished it as the number 46.
2014/2015 season He came close to reaching the quarter-finals of the
Wuxi Classic for the second season in a row, after he defeated
Mark King 5–1 and
Ricky Walden 5–3, stating that he done some body building, jogging and gym work to try to improve his game. He lost 5–1 to
Robin Hull in the last 16. He was knocked out in the first round of the
UK Championship 6–4 by
Lyu Haotian and beat
Craig Steadman 4–2 at the
Welsh Open. He won two frames to force a decider in the second round against Mark Allen, which Cao lost. Cao also qualified for the
Indian Open and
China Open, but was eliminated in the first round of both.
2015/2016 season Cao qualified for the
International Championship with a 6–2 win over
Liam Highfield, but was beaten 6–2 by
Tian Pengfei in the first round. He could only win a total of four matches all season, finishing 72nd in the world rankings. This meant that Cao had to enter
Q School and he earned his place back on the tour at the first event with five match wins.
2016/2017 season Cao was on a losing streak of 11 matches until he played in the
Shoot-Out where he knocked out three players, before being defeated by David Grace. Aside from that, he only won two matches during the season.
2017/2018 season Cao notched his first-ever maximum break in tournament play in the second round of the Scottish Open. He became only the third player from mainland China to achieve the feat, following Ding Junhui and
Liang Wenbo. Cao later reached the final of the Scottish Open, the first ranking final in his career. He built up a lead of 8–4 until his opponent, Neil Robertson, won the final five frames in dramatic fashion to defeat Cao by 9–8. In the same season Cao reached the semi-finals of the
European Masters (losing to eventual champion
Judd Trump) and his second final, the
Gibraltar Open, where he lost 4–0 to Ryan Day. He was suspended from the tour on 25 May 2018, alongside
Yu Delu and
David John, pending an investigation into suspected match fixing. After admitting to fixing three matches in 2016, Cao was suspended from professional play for thirty months by the
WPBSA.
2020/2021 season Cao's ban expired in November 2020, but he was unable to play in the professional circuit as a top-up so entered into the CBSA China Tour. He regained his professional tour card having defeated Liu Hongyu 4–3 in the CBSA China Tours' second qualifying event, alongside former professional
Zhang Anda.
2021/2022 season Despite having been suspended from the World Snooker Tour for three years, Cao had a relatively good start to his campaign in the
2021 Championship League and the
2021 British Open, with good performances in his matches throughout the season as a whole. Although he did not progress past the third round of any tournament, he had reached the cusp of the Top 64 by the
2022 World Snooker Championship, being seeded 70th in the qualifying round. ==Personal life==