The 2000 United States Open Championship was the 100th U.S. Open Championship, held June 15–18 at Pebble Beach Golf Links in Pebble Beach, California. Tiger Woods won his first U.S. Open by a record-setting fifteen strokes over runners-up Ernie Els and Miguel Ángel Jiménez – it remains the most dominating performance and victory in any major championship. As the United States Golf Association wanted to begin the millennium with a memorable tournament, Pebble Beach was moved up two years in the rotation. Notable golfers going into the tournament at large included Jack Nicklaus, playing in his final U.S. Open; Vijay Singh, the year's Masters winner; Ernie Els; and David Duval.

The United States Open Championship, commonly known as the U.S. Open, is the annual open national championship of golf in the United States. It is the third of the four men's major golf championships, and is on the official schedule of both the PGA Tour and the European Tour. Since 1898 the competition has been 72 holes of stroke play, with the winner being the player with the lowest total number of strokes. It is staged by the United States Golf Association (USGA) in mid-June, scheduled so that, if there are no weather delays, the final round is played on the third Sunday. The U.S. Open is staged at a variety of courses, set up in such a way that scoring is very difficult, with a premium placed on accurate driving. As of 2023, the U.S. Open awards a $20 million purse, the largest of all four major championships.