He was voted WPBSA Newcomer of the Year and WSA Young Player of the Year in 1999. Tipped by many pundits as a potential champion of the game, Fu's subsequent performance was disappointing, and he slid back down the rankings.
Fu is a prolific break-builder. He achieved his highest break of 147 in 2000 at the Regal Scottish Masters and has compiled 147 competitive century breaks during his career.
The 2000/01 season bought more good news for Fu, he was now ranked 15th in the world, his first appearance in the top 16. However a succession of defeats in the last 16 and a first round defeat in the World Snooker Championships to Chris Small saw him fall out of the top 16 for next season. The 2001/02 season was a terrible season for Fu, his best result reaching last 16 at the LG Cup. He failed to qualify for three ranking events, including the World Championship, and as a result his ranking fell to 27 for the following season, his lowest for two seasons.
The 2002/03 season bought better luck for Fu, although prior to the Welsh Open his best result was reaching the third round of the UK Championship. However, at the Welsh Open, he produced a run to the semi finals. Fu whitewashed Stephen Lee 5-0 in the quarter-finals before losing his semi-final 6-4 to Stephen Hendry, who went on to win the title.
Going into the 2003 World Championship three months later, first round losses at the European and Scottish Open suggested he would not go far in the tournament. However, Fu reached the first of his two World Championship quarter-finals to date. In what Snooker Scene magazine described as "one of the greatest upsets in the history of the game", the unseeded 25-year-old knocked out world No. 1 and runaway favourite Ronnie O'Sullivan in the first round of the tournament. Fu dominated this match from the outset, opening up a 6-3 overnight lead; and although O'Sullivan made three (including a maximum 147 break) while recovering, Fu never looked to be in trouble and won 10-6. Fu subsequently eliminated Alan McManus 13-7 in the second round before losing 13-9 to Stephen Lee in his quarter-final.
The following season was less consistent, however, he qualified for all tournaments but the Malta Cup, and his best result was a quarter final loss to Ding Junhui at the China Open. He finished the season ranked 25, falling seven places. The 2005/06 season did not look better either, a series of first round defeats saw him provisionally drop out of the top 32. However, he had a good 2006 World Championship, beating three seeded players - Alan McManus 10-3, Stephen Maguire 13-4, and Ken Doherty 13-10 - to reach the semi-finals, where he lost to world no.7 and 2002 world champion Peter Ebdon 17-16. In that match, Fu was 15-9 down with only one session left to play, but won seven out of the next eight frames to send the match into the deciding frame, which Ebdon eventually won. Fu's success in this tournament can be largely attributed to working with coach Terry Griffiths. Marco had used Griffiths for a short while some years ago - but did not commit to the necessary changes in technique. This run enable him to stay in the world top 32 for next season, ranked 22.
The 2006/07 season was not hugely successful. He skipped the UK Championship
to play in the Asian games (winning two medals there), and, largely due to the fact that he was affected by a virus, was unable to repeat his World Championship form of the previous year, losing 10-3 to Anthony Hamilton in the first round, a defeat that saw Fu start the 2007/2008 season ranked 27th in the world - a drop of five places. His best result that season was a quarter final run in the China Open, where he lost to Ronnie O'Sullivan.
The 2007/08 season was to bring his first ranking title. Following a first round loss at the Shanghai Masters and nine years after his first appearance in a ranking final at the 1998 Grand Prix, Fu won the 2007 Royal London Watches Grand Prix — his first ever victory in a ranking event. After defeating the reigning World Champion John Higgins in the first knockout round 5-4, Liu Song 5-0 in the quarter-final and Gerard Greene 6-5 in the semi-final, he faced Ronnie O'Sullivan in the final. After falling 4-3 behind at the mid-session interval, he went on to win 9-6, with a break of 76 in the final frame. Previously, Fu’s biggest title has been the invitational Hasseroder Premier League which he captured in 2003, beating Mark Williams 9-5 in the final in Sunderland. This was the first time the title went outside of the British Isles. For the rest of the season, he reached the quarter finals of the UK Championship, losing to Mark Selby; he also reached the semi finals of the Masters, losing to Stephen Lee.
He qualified for the 2008 World Championship, with a 10-3 win over Alan McManus . He played China's Ding Junhui in the first round of 2008 World Championship, and it was an emphatic fight, which he lost 10-9. He caped a successful season by finishing a career high 14 in the rankings, a climb of thirteen places from the previous season. This guaranteed Fu automatic a bye to the main draw of tournaments next season without playing qualifying matches, as well as being seeded.