Marienville, PA has a population of 4,673 and is the 6,765th largest city in the United States. The population density is 773 per sq mi which is 179% higher than the Pennsylvania average and 753% higher than the national average. The median age in Marienville is 36 which is approximately 12% lower than the Pennsylvania average of 41. In Marienville, 21% of the population over 15 years of age are married, 88% speak English and 8% speak Spanish. 84% of Marienville residents were born in Pennsylvania, 12% were born out of state, 2% were born outside of the United States and 3% were foreign born.