Quintana Roo (pronounced [kinˈtana ˈro]) is a state of Mexico, on the eastern part of the Yucatán Peninsula. It borders the States of Yucatán and Campeche to the north and west, the Caribbean Sea to the east, and the nation of Belize to the south. Quintana Roo also claims territory which gives it a small border with Guatemala in the south west of the state, although this disputed area is also claimed by Campeche.

The capital of Quintana Roo is the city of Chetumal. Quintana Roo also contains the resort city of Cancún, the islands of Cozumel and Isla Mujeres, the towns of Bacalar, Felipe Carrillo Puerto, Playa del Carmen, Puerto Juárez, Akumal, Xcalak, and Puerto Morelos, as well as the ancient Maya ruins of Chacchoben, Chakanbakán, Chamax, Coba, Dzibanché, El Meco, Ichpaatán, Kohunlich, Muyil, Oxtankah, Tancah, Tulum, Tupak, Xel-Há, and Xcaret. The Sian Ka'an Biosphere Reserve is also in Quintana Roo.

The state covers an area of 50,351 square kilometers (19,440.6 sq mi), and the 2005 census reported a population of 1,135,309. The statewide population is currently expanding at a rapid rate due to the construction of hotels and the demand for workers. Many immigrants to the state come from Yucatán, Campeche, Tabasco, and Veracruz. The state, known as a resort area, is frequently hit by severe hurricanes due to its exposed location.