There were at least four special elections to the United States House of Representatives in 1965, during 89th United States Congress.
Elections are listed by date and district.
|- ! | Albert Watson | | Democratic | 1962 | | Incumbent resigned February 1, 1965, after being stripped of seniority by the House Democratic Caucus for supporting Republican presidential candidate Barry Goldwater.<br/>Incumbent re-elected June 15, 1965 as a Republican.<br/>Republican gain. | nowrap |
|- ! | Ashton Thompson | | Democratic | 1952 | | Incumbent died July 1, 1965.<br/>New member elected October 2, 1965.<br/>Democratic hold. | nowrap |
|- ! | Clarence J. Brown | | Republican | 1938 | | Incumbent died August 23, 1965.<br/>New member elected November 2, 1965.<br/>Republican hold. | nowrap |
|- ! | James Roosevelt | | Democratic | 1954 | | Incumbent resigned to run for Mayor of Los Angeles.<br/>New member elected December 15, 1965.<br/>Democratic hold. | nowrap |