Junction City is a census-designated place (CDP) in Grays Harbor County, Washington, United States.

U.S. Route 12 runs along the northern edge of the CDP, leading west into Aberdeen and east 18 miles (29 km) to Elma.

Olympia is 49 miles (79 km) to the east of Junction City via U.S. 12 and State Route 8.

33.3% of all households were made up of individuals, and 11.1% had someone living alone who was 65 years of age or older.

There were no families and 22.1% of the population living below the poverty line, including no under eighteens and none of those over 64.