The 2006 United States Senate election in Indiana was held November 7, 2006. Incumbent Republican United States Senator Richard Lugar was re-elected to his sixth six-year term with 87.3% of the vote. He did not have a Democratic opponent and only faced opposition from a Libertarian candidate; this was the only U.S. Senate race in 2006 in which Democrats did not field a candidate. This would be the last successful race of Lugar's decades long political career. This is also the last time that Lake, Marion, and Monroe counties have voted for a Republican candidate for Senate.

Richard Green Lugar KBE was an American politician who served as a United States Senator from Indiana from 1977 to 2013. He was a member of the Republican Party.