Marion County incorporates all or part of about 20 Oregon Cities
- Aumsville
- Aurora
- Detroit
- Donald
- Gates (part)
- Gervais
- Hubbard
- Idanha (part)
- Jefferson
- Keizer
- Mill City (part)
- Mt. Angel
- St. Paul
- Salem (county seat)
- Scotts Mills
- Silverton
- Stayton
- Sublimity
- Turner
- Woodburn