| Election Name: | 1920 United States Senate election in Iowa |
| Country: | Iowa |
| Type: | presidential |
| Ongoing: | no |
| Election Date: | November 2, 1920 |
| Previous Election: | 1914 United States Senate election in Iowa |
| Previous Year: | 1914 |
| Next Election: | 1926 United States Senate elections in Iowa |
| Next Year: | 1926 |
| Image1: | File:Albert Baird Cummins circa 1917 (1).jpg |
| Nominee1: | Albert B. Cummins |
| Party1: | Republican Party (US) |
| Popular Vote1: | 528,499 |
| Percentage1: | 61.42% |
| Nominee2: | Claude R. Porter |
| Party2: | Democratic Party (US) |
| Popular Vote2: | 322,015 |
| Percentage2: | 37.42% |
| Map Size: | 250px |
| U.S. senator | |
| Before Election: | Albert B. Cummins |
| Before Party: | Republican Party (US) |
| After Election: | Albert B. Cummins |
| After Party: | Republican Party (US) |
The 1920 United States Senate election in Iowa was held on November 2, 1920. Incumbent Senator Albert B. Cummins was re-elected to a third term in office, defeating challenges from Smith W. Brookhart in the Republican primary and Claude R. Porter in the general election.
Albert B. Cummins was a progressive senator from an earlier generation who distrusted both corporate interests and trade unions. Brookhart campaigned against railroad regulations Cummins had co-authored, the Esch–Cummins Act, which Brookhart claimed did too little to wrest ownership and control of railroads away from Wall Street interests.[1] Brookhart attempted to register rank-and-file blue-collar workers as Republicans so that they could vote for him in the primary,[1] which prompted Cummins to associate Brookhart with radical workers movements such as "the Socialists, reds and Industrial Workers of the World."[2] Cummins was sidelined by illness in the weeks leading up to the primary but defeated Brookhart.[2] [3]