His favorite surface is hardcourt, though several of his ATP Tour career highlights came on grass, including reaching the quarterfinals of the 2010 Wimbledon Championships.

In his junior career, he compiled a singles win–loss record of 80–37 (63–34 in doubles) and defeated a handful of future ATP stars, including Robin Söderling, Mario Ančić, and Philipp Kohlschreiber.

[2] His result in Junior Grand Slam events are as follows: In 2004, Lu became the first player from Taiwan to break into the ATP top 100, thanks to a solid performance in the Challenger Tour in the first half of 2004.

The training seemed to yield good results, as Lu reached the second round at the Australian Open and his first ATP level quarter-final in Memphis in 2007.

By defeating Jürgen Melzer in the second round, Lu reached his first ATP level quarter-final, but lost to eventual finalist Andy Roddick.

Lu shocked audiences by defeating then sixth ranked player in the world, Andy Murray, in straight sets in the first round.

In May 2009, Lu won the $100k Israel Open at Ramat HaSharon, beating German Benjamin Becker, who was forced to retire.

[5] In November 2009, Lu won the $100k Flea Market Cup at Chuncheon, beating Dutch player Igor Sijsling.

He started the Odlum Brown Vancouver Open as the number one seeded player, defeating George Bastl in the first round before losing to Alex Bogdanovic.

On 15 June 2012, Lu clinched a huge maiden victory with a third set tie-break triumph over third seed Janko Tipsarević to reach the quarter-finals at Queen's Club.

During the 2014 Asian Games, the ATP threatened to fine and ban Lu for three years if he did not report to the China Open on September 29.

He had signed up to participate in both events, but the final for the Asian Games did not take place until September 30, a schedule conflict the ATP would not accommodate.

[citation needed] At the Miami Open, Lu recorded his last ATP match win against Sam Querrey.

In June 2021, after playing a few more ATP matches, Lu announced that he would retire from tennis and that the 2021 Wimbledon Championships and the 2021 Tokyo Olympics would be his last tournaments on the tour.

[18] On 25 July 2021, Lu played his last career tennis match at the Olympics against Alexander Zverev where he lost in straight sets.

[20] Lu was sponsored by adidas (apparel and shoes), Head (rackets), Chunghwa Telecom and CPC Corporation.