Dutch Island is an island lying west of Conanicut Island at an entrance to Narragansett Bay in Rhode Island, United States. It is part of the town of Jamestown, Rhode Island, and has a land area of 0.4156 km². It was uninhabited as of the United States Census, 2000. The island was fortified from the American Civil War through World War II and was known as Fort Greble from 1898 to 1947.