Marysville, CA has a population of 12,176 and is the 3,378th largest city in the United States. The population density is 3,515 per sq mi which is 1413% higher than the California average and 3780% higher than the national average. The median age in Marysville is 31 which is approximately 15% lower than the California average of 36. In Marysville, 51% of the population over 15 years of age are married, 81% speak English and 14% speak Spanish. 72% of Marysville residents were born in California, 16% were born out of state, 1% were born outside of the United States and 11% were foreign born.