The 2016 presidential campaign of Gary Johnson, the 29th Governor of New Mexico, was announced on January 6, 2016, for the nomination of the Libertarian Party (or LP) for President of the United States. He officially won the nomination on May 29, 2016, at the Libertarian National Convention in Orlando, Florida, receiving 56% of the vote on the second ballot. Former Massachusetts Governor William Weld was endorsed by Johnson for the Libertarian vice-presidential nomination, which he also received on May 29, 2016.

Johnson and Weld formed the first ticket of any party to feature two governors since the 1948 presidential election. They received 3.3% of the vote, totaling nearly 4.5 million, dwarfing Johnson's 2012 popular vote total and marking the Libertarians' most successful presidential run to date and the most successful third-party candidacy since Ross Perot in 1996.