Marmaduke is a city located in the U.S. state of Arkansas. It is within and the county seat of Greene County approximately 11 miles southwest to Paragould. It has a total land area of 1.30 square miles at 36°11′22″N 90°23′8″W. The elevation is 279 feet above sea level. As of the 2010 census data, it had a total population of 1,111. The population density was 935.63/sq mi. Estimated per capita income in 2015 was $15,425. It is using Zip codes 72436 and 72443.