is a town in Newport County, Rhode Island, United States. The population was 17,335 at the 2000 census. It lies to the south of Portsmouth and to the north of Newport on Aquidneck Island, hence the name "Middletown."
According to the United States Census Bureau, the town has a total area of 14.9 square miles (38.7 km²), of which 13.0 square miles (33.6 km²) is land and 2.0 square miles (5.1 km²)(13.18%) is water. Middletown is known as the "farming community" of Aquidneck Island, today about 45% of the town is farm land, 25% is wooded, and about 30% is developed of its 14.9 square miles. Most of the developed land is located towards the southern part of the town near Newport while the rural area is towards the North near Portsmouth. Middletown also is known to have some of the best beaches in New England.