Misiones is one of the 23 provinces of Argentina, located in the northwestern corner of the country. Area: 29,801 km². Population: 963,869 (2001). Capital city: Posadas.

It is surrounded by Paraguay to the northwest, Brazil to the north and east, and Corrientes Province of Argentina to the southwest.

The Iguaçú Falls are waterfalls located on the border of Brazilian state of Paraná (in the Southern Region) and the Argentinian Province of Misiones.

The province is named after the Jesuit missions (Reducciones), which were established in the area. Of the 15 Reducciones established in Argentina, 11 were located in the present Misiones Province. Of these 11, 4 have been listed as UNESCO's World Heritage Sites in 1984: San Ignacio Mini, Nuestra Señora de Santa Ana, Nuestra Señora de Loreto, Santa María la Mayor.

There is also a Misiones department in neighboring Paraguay.