Marietta CDP, OK has a population of 149 and is the 25,684th largest city in the United States. The population density is 82 per sq mi which is 51% higher than the Oklahoma average and 9% lower than the national average. The median age in Marietta CDP is 28 which is approximately 24% lower than the Oklahoma average of 36. In Marietta CDP, 44% of the population over 15 years of age are married, 84% speak English and 16% speak Spanish. 78% of Marietta CDP residents were born in Oklahoma, 22% were born out of state, 0% were born outside of the United States and 0% were foreign born.