The 2000 United States presidential election was the 54th quadrennial presidential election, held on Tuesday, November 7, 2000. Republican candidate George W. Bush, the governor of Texas and eldest son of the 41st president, George H. W. Bush, won the election, defeating incumbent Vice President Al Gore. It was the fourth of five American presidential elections, and the first since 1888, in which the winning candidate lost the popular vote, and is considered one of the closest elections in US history, with longstanding controversy surrounding the ultimate results.Incumbent Bill Clinton was ineligible for a third term, and Gore secured the Democratic nomination with relative ease, defeating a challenge by former Senator Bill Bradley. Bush was seen as the early favorite for the Republican nomination and despite a contentious primary battle with Senator John McCain and others, secured the nomination by Super Tuesday. Bush chose former Secretary of Defense Dick Cheney as his running mate, while Gore chose Senator Joe Lieberman.

Both major-party candidates focused primarily on domestic issues, such as the budget, tax relief, and reforms for federal social insurance programs, although foreign policy was not ignored. Due to President Bill Clinton's sex scandal with Monica Lewinsky and subsequent impeachment, Gore avoided campaigning with Clinton. Republicans denounced Clinton's indiscretions, while Gore criticized Bush's lack of experience. On election night, it was unclear who had won, with the electoral votes of the state of Florida still undecided. The returns showed that Bush had won Florida by such a close margin that state law required a recount. A month-long series of legal battles led to the highly controversial 5–4 Supreme Court decision Bush v. Gore, which ended the recount.

The recount having been ended, Bush won Florida by 537 votes, a margin of 0.009%. The Florida recount and subsequent litigation resulted in major post-election controversy, and with speculative analysis suggesting that limited county-based recounts would likely have confirmed a Bush victory, whereas a statewide recount would likely have given the state to Gore. Ultimately, Bush won 271 electoral votes, one vote more than the 270-to-win majority, despite Gore receiving 543,895 more votes (a margin of 0.52% of all votes cast). Bush won 11 states that had voted Democratic in the 1996 election: Arkansas, Arizona, Florida, Kentucky, Louisiana, Missouri, Nevada, New Hampshire, Ohio, Tennessee and West Virginia.

As of 2022, this is the earliest election in which both major-party presidential and vice-presidential candidates are still living.