| Election Name: | 1861 United States Senate election in California |
| Type: | presidential |
| Ongoing: | no |
| Flag Image: | First Bear Flag of California (1846).svgborder |
| Previous Election: | 1857 United States Senate special election in California |
| Previous Year: | 1857 (special) |
| Next Election: | 1865 United States Senate election in California |
| Next Year: | 1865 |
| Election Date: | April 2, 1861 |
| Votes For Election: | Majority vote of both houses needed to win |
| 1Blank: | Joint session |
| 2Blank: | Percentage |
| Image1: | Hon. James A. McDougall, Ill - NARA - 527723 3x4.jpg |
| Nominee1: | James A. McDougall |
| Party1: | Democratic Party (United States) |
| 1Data1: | 57 |
| 2Data1: | 54.81% |
| Nominee2: | John Nugent |
| Party2: | Southern Democratic (United States) |
| 1Data2: | 39 |
| 2Data2: | 37.50% |
| Senator | |
| Before Election: | William M. Gwin |
| Before Party: | Democratic Party (United States) |
| After Election: | James A. McDougall |
| After Party: | Democratic Party (United States) |
The 1861 United States Senate election in California was held on April 2, 1861, by the California State Legislature to elect a U.S. Senator (Class 3) to represent the State of California in the United States Senate. In a special joint session, former Democratic Congressman James A. McDougall was elected over Southern Democratic newspaper editor John Nugent.[1] McDougall was elected with Republican support.[2]