John Day
- Country: United States
- State: Oregon
- Population: 1,674 (2016)
- Latitude: 44° 25' N (44.41599°)
- Longitude: 118° 57.2' W (-118.95301°)
- Elevation: 941 m/3,086 ft. above sea level
- Time zone: America/Los_Angeles (UTC -08:00); DST observed (UTC -07:00)