Marmari (Greek: Μαρμάρι, Katharevousa: Μαρμάριον) is a village and a former municipality in Euboea, Greece, in the southeastern end of the island. Since the 2011 local government reform it is part of the municipality Karystos, of which it is a municipal unit. The Greek National Road 44 (Chalkida - Karystos) runs through Marmari. There are ferry routes with the mainland port of Rafina. The mountains dominate the east. Its main economy are businesses and agriculture. Marmari is located SE of Chalkida, E of Rafina and west of Karystos.
Marmari currently has two schools: a middle school and a junior high school. Marmari is surrounded by beautiful beaches which frequently host surfers from across the globe. Marmari is also home to Eastern Orthodox Christian churches. Marmari is also home to a post office,as well as many taverns. It is approximately one hour away from the port city of Rafina.