| Election Name: | 1916 United States Senate election in California |
| Country: | California |
| Type: | presidential |
| Flag Image: | Flag of California (1911–1924).pngborder |
| Ongoing: | no |
| Previous Election: | 1911 United States Senate election in California |
| Previous Year: | 1911 |
| Next Election: | 1922 United States Senate election in California |
| Next Year: | 1922 |
| Election Date: | November 7, 1916 |
| Image1: | File:Souvenir of the unveiling, dedication and presentation of the Abraham Lincoln G. A. R. memorial monument - dedicated to the veterans of the Civil War, 1861-1865, at Long Beach, California, July 3rd, (14576262447).jpg |
| Nominee1: | Hiram Johnson |
| Party1: | Republican Party (US) |
| Alliance1: | Progressive Party (US, 1912) |
| Popular Vote1: | 574,667 |
| Percentage1: | 61.09% |
| Nominee2: | George S. Patton |
| Party2: | Democratic Party (US) |
| Popular Vote2: | 277,852 |
| Percentage2: | 29.54% |
| Image3: | File:Mills-Walter-Thomas-1904.jpg |
| Nominee3: | Walter Thomas Mills |
| Party3: | Socialist Party of America |
| Popular Vote3: | 49,341 |
| Percentage3: | 5.25% |
| Map Size: | 300px |
| U.S. Senator | |
| Before Election: | John Downey Works |
| Before Party: | Republican Party (United States) |
| After Election: | Hiram Johnson |
| After Party: | Republican Party (United States) |
The 1916 United States Senate election in California was held on November 6, 1916. Incumbent Senator John Downey Works did not run for re-election.
Governor of California and 1912 Progressive Party vice presidential nominee Hiram Johnson won the open seat, defeating Democratic attorney and Mayor of San Marino George Patton.
George Patton was unopposed on the ballot, but Hiram Johnson, Willis Booth, and Walter Thomas Mills received write-in votes.
Gov. Hiram Johnson was unopposed on the primary ballot, but Willis Booth did receive write-in votes.
Walter Thomas Mills was unopposed on the primary ballot, but Hiram Johnson and Willis Booth received write-in votes.
Atwood was unopposed on the primary ballot, but Hiram Johnson and Willis Booth received write-in votes.