The Dominican Republic (Spanish: República Dominicana) is a country in the West Indies that occupies the eastern five-eighths of Hispaniola. It has an area of 48,670 km², including offshore islands. The land border shared with Haiti, which occupies the western three-eighths of the island, is 376 km long. The maximum length, east to west, is 390 km from Punta de Agua to Las Lajas, on the border with Haiti. The maximum width, north to south, is 265 km from Cape Isabela to Cape Beata. The capital, Santo Domingo, is located on the south coast.

The Dominican Republic's shores are washed by the Atlantic Ocean to the north and the Caribbean Sea to the south. The Mona Passage, a channel about 130 km wide, separates the country (and Hispaniola) from Puerto Rico.