The 2000 Cincinnati Masters was a men's tennis tournament and the 99th edition of the event previously known as the Great American Insurance ATP Championships. The tournament was part of the Tennis Masters Series of the 2000 ATP Tour. It took place in Mason, Ohio, United States, from August 7 through August 14, 2000. Thomas Enqvist won the singles title.
The tournament previously appeared on the Tier III of the WTA Tour; no event was held from 1989 to 2003.
See main article: 2000 Cincinnati Masters – Singles. 
Thomas Enqvist defeated 
Tim Henman, 7–6(7–5), 6–4
See main article: 2000 Cincinnati Masters – Doubles. 
Mark Woodforde / Todd Woodbridge defeated Ellis Ferreira / 
Rick Leach 7–6(8–6), 6–4