| Election Name: | 1984 United States Senate election in Oregon |
| Country: | Oregon |
| Flag Year: | 1956 |
| Type: | Presidential |
| Ongoing: | no |
| Previous Election: | 1978 United States Senate election in Oregon |
| Previous Year: | 1978 |
| Next Election: | 1990 United States Senate election in Oregon |
| Next Year: | 1990 |
| Election Date: | November 6, 1984 |
| Image1: | File:Mark hatfield (cropped).jpg |
| Nominee1: | Mark Hatfield |
| Party1: | Republican Party (United States) |
| Popular Vote1: | 808,152 |
| Percentage1: | 66.53% |
| Nominee2: | Margie Hendriksen |
| Party2: | Democratic Party (United States) |
| Popular Vote2: | 406,122 |
| Percentage2: | 33.43% |
| Map Size: | 250px |
| U.S. Senator | |
| Before Election: | Mark Hatfield |
| Before Party: | Republican Party (United States) |
| After Election: | Mark Hatfield |
| After Party: | Republican Party (United States) |
The 1984 United States Senate election in Oregon took place on November 6, 1984. Incumbent Republican U.S. Senator Mark Hatfield was re-elected to a fourth term in office, defeating Democratic State Senator Margie Hendriksen. As of 2022, this is the last U.S. Senate race in Oregon where every county voted for the same candidate.
During the campaign, Hendriksen primarily attacked Hatfield by stressing what she perceived to be flawed priorities.[1] Hatfield was often criticized for the scandal involving Basil Tsakos, but the controversy of the scandal declined over the course of the campaign.[2] He was also criticized by those who stressed environmental protection for his support of President Reagan's appointment of James G. Watt to the position of Secretary of the Interior.[3] However, Hatfield's in-person campaign strategy proved successful, as he beat Hendricksen by 402,040 votes, and gained nearly double her percentage.