2008 Tennis Masters Cup

The 2008 Tennis Masters Cup was a tennis tournament played on indoor hard courts. It was the 39th edition of the year-end singles championships, the 34th edition of the year-end doubles championships, and part of the 2008 ATP Tour. It took place at the Qizhong Forest Sports City Arena in Shanghai, China, from November 9 through November 16, 2008.

Association of Tennis Professionals (ATP) No. 3 Novak Djokovic of Serbia won his first year-end championships title in the singles event, defeating ATP No. 5 Nikolay Davydenko of Russia in the final 6–1, 7–5. Four-time winner, two-time defending champion Roger Federer was defeated in the round robin stage of the event for the first time in seven consecutive appearances. Daniel Nestor of Canada and Nenad Zimonjić of Serbia won the doubles event 7–6, 6–2 over Americans Bob and Mike Bryan in the final for their first year-end championships doubles title together. With the win, they clinched the year-end No. 1 spot for the first time together. Nestor successfully defended his 2007 Tennis Masters Cup title with his new partner Zimonjić, while the other defending champion, Mark Knowles, lost in the round robin, with Mahesh Bhupathi.

It was the last time that the singles and doubles year-end championships took place in Shanghai as the Tennis Masters Cup. Starting in 2009, the season-ending event will be moved to London, United Kingdom, at the O₂ arena, under the new name of ATP World Tour Finals. Shanghai will instead hold a new event in the 2009 season, the Shanghai Masters, which will take place earlier in the year.