Junction City, CA has a population of 675 and is the 17,685th largest city in the United States. The population density is 24 per sq mi which is 90% lower than the California average and 73% lower than the national average. The median age in Junction City is 59 which is approximately 63% higher than the California average of 36. In Junction City, 68% of the population over 15 years of age are married, 94% speak English and 4% speak Spanish. 57% of Junction City residents were born in California, 32% were born out of state, 0% were born outside of the United States and 11% were foreign born.