Elon Musk has been actively involved in politics, particularly in the United States and Europe, throughout the majority of his business career. Despite historically donating to and voting for both Democrats and Republicans, his political contributions have since shifted almost entirely to right-wing candidates and politicians, outright stating in 2022 that he would no longer support Democrats. In the time since, Musk has become more vocal about his views, frequently promoting falsehoods about election fraud. As a result, he has been described as conservative, although he rejects the label and calls himself a moderate.

Musk played a significant role in the 2024 United States presidential election by establishing a political action committee (PAC) in support of Donald Trump for his campaign, making him the election's largest donor with over US$250 million. Following Trump's 2024 victory, Musk was appointed to co-run a new temporary government organization popularly known as the Department of Government Efficiency (DOGE), serving until May 2025, when Musk departed from the department.

In 2024, he started supporting international far-right political parties, activists, and causes. An NBC News analysis found he had boosted far-right political movements to cut immigration and curtail regulation of business in at least 18 countries on six continents since 2023. His international political activities have been scrutinized, particularly in Europe, with some saying his actions and comments appear as "foreign interference" in domestic affairs. Musk's comments and actions have received increasing criticism from some of the governments and leaders of European countries, in particular regarding his support of Alternative for Germany during the 2025 German federal elections.

Musk became a U.S. citizen in 2002, founding SpaceX that year using his share of the profits from PayPal's sale to eBay. From 2008 to 2013, Musk flew to Washington, D.C. forty times, according to biographer Ashlee Vance. At a Vanity Fair event with Y Combinator president Sam Altman in 2015, Musk said he was "involved in politics as little as possible". Prior to the 2016 United States presidential election, Musk donated to Hillary Clinton and later said he voted for her. In November 2016, Musk criticized Donald Trump as "not the right guy" in an interview with CNBC. The following month, Trump appointed Musk to his Strategic and Policy Forum. Musk later endorsed Trump for the 2024 United States presidential election.

A 2012 report from the Sunlight Foundation, a nonpartisan group that tracks government spending, found that since 2002, SpaceX had spent more than $4 million on lobbying the United States Congress and more than $800,000 in political contributions to Democrats and Republicans. As for Musk specifically, the same report said that "SpaceX's campaign to win political support has been systematic and sophisticated," and that "unlike most tech-startups, SpaceX has maintained a significant lobbying presence in Washington almost since day 1" and that "Musk himself has donated roughly $725,000 to various campaigns since 2002. In 2004, he contributed $2,000 to President George W. Bush's reelection campaign, maxing out (over $100,000) to Barack Obama's reelection campaign and donated $5,000 to Republican Sen. Marco Rubio, who represents Florida, a state critical to the space industry. [...] All told, Musk and SpaceX gave out roughly $250,000 in the 2012 election cycle."

In 2017, Musk made his public first entry into major American politics, speaking at the National Governors Association at the invitation of Brian Sandoval.

By January 2017, Musk had met with Trump at Trump Tower to argue for the SpaceX Mars colonization program. That month, he told Gizmodo that he was among several "voices of reason" for Trump. In June, he resigned from his positions on Trump's advisory councils after the United States withdrew from the Paris Agreement. Musk donated US$50,000 to an organization benefiting Republican members of the House of Representatives and an additional US$38,900 to a separate group ahead of the 2018 House of Representatives elections, defending his decision in order to "maintain dialogue". The following year, he offered an endorsement of Andrew Yang's presidential campaign and tacitly supported Kanye West's campaign in the 2020 presidential election, but said that he attempted to convince West to postpone his campaign in an interview with Maureen Dowd.

Speaking to Kara Swisher in September 2020, Musk considered voting for Trump if Joe Biden was not a viable candidate, though he later said he voted for Biden. In May 2022, Musk stated that the Democratic Party had become the "party of division and hate" and that he would vote for Republicans, later urging voters vote for Republicans in that year's midterm elections in order to counter a Democratic presidency.