Grant County is one of the 36 counties in the U.S. state of Oregon. As of the 2020 census, the population was 7,233, making it Oregon's fourth-least populous county. The county seat is Canyon City. It is named for President Ulysses S. Grant, who served as an army officer in the Oregon Territory, and at the time of the county's creation was a Union general in the American Civil War.

Canyon City is a city in Grant County, Oregon, United States. It is the county seat of Grant County, and is about 2 miles (3 km) south of John Day on U.S. Highway 395. As of the 2010 census, the city had a total population of 703.