| Election Name: | 2020 Oregon State Senate election |
| Percentage2: | 44.4% |
| Ongoing: | no |
| Previous Election: | 2018 Oregon state elections |
| Previous Year: | 2018 |
| Next Election: | 2022 |
| Next Year: | 2022 |
| Seats For Election: | 16 of 30 seats in the Oregon State Senate |
| Image2 Size: | 160x160px |
| Majority Seats: | 16 |
| Leader2: | Herman Baertschiger Jr. |
| Party2: | Republican Party (United States) |
| Leader Since2: | January 22, 2019 |
| Leaders Seat2: | District 2 (Grants Pass) |
| Last Election2: | 12 seats, 37.9% |
| Seats Before2: | 12 |
| Seats2: | 12 |
| Type: | legislative |
| Country: | Oregon |
| Party1: | Democratic Party (United States) |
| Leader Since1: | May 22, 2020 |
| Leaders Seat1: | District 19 (Lake Oswego) |
| Last Election1: | 18 seats, 62.1% |
| Seats Before1: | 18 |
| Seats1: | 18 |
| Percentage1: | 54.0% |
| Image1 Size: | 160x160px |
| Image1: | File:Rob Wagner.jpg |
| President of the Senate | |
| Before Election: | Peter Courtney |
| Before Party: | Democratic |
| After Election: | Peter Courtney |
| After Party: | Democratic |
| Popular Vote1: | 628,347 |
| Popular Vote2: | 516,030 |
| Swing1: | 8.1% |
| Leader1: | Rob Wagner |
| Swing2: | 6.5% |
| Map Size: | 350px |
The 2020 Oregon State Senate election was held on Tuesday, November 3, 2020, with the primary election being held on May 19, 2020. Voters in 16 of the 30 Oregon State Senate districts elected their state senators. The elections coincided with the elections for other offices, including for U.S. President.
The Democratic Party kept their majority.[1] The Oregon State Senate does not have term limits.
Democrats had held the Oregon Senate since 2002 and the chamber was not considered competitive in 2020.
Members of the Oregon State Senate are elected from single-member districts by first-past-the-post voting to four-year terms with staggered elections. Contested nominations of the Democratic and Republican parties for each district were determined by an open primary election. Minor-party and independent candidates were nominated by petition, and write-in candidates had to file a request with the Secretary of State's office for votes for them to be counted.
| Democratic | 16 | 628,347 | 54.01% | 18 | 7 | 7 | 18 | ||
| Republican | 12 | 516,030 | 44.36% | 12 | 9 | 9 | 12 | ||
| Libertarian | 3 | 6,694 | 0.58% | 0 | 0 | 0 | 0 | ||
| Pacific Green | 1 | 3,107 | 0.27% | 0 | 0 | 0 | 0 | ||
| Total valid votes | 32 | 1,154,178 | 99.21% | 30 | 16 | 16 | 30 | ||
|---|---|---|---|---|---|---|---|---|---|
Districts where the margin of victory was under 10%: