Guaira may refer to:
Guayrá, a former region of the Spanish Empire in what is now modern Paraguay and Brazil Guaíra Falls, former waterfalls on the Paraná River along the border between Brazil and Paraguay Brazil Guaíra, Paraná Guaíra Airport Guaíra, São Paulo Paraguay Guairá Department Salto del Guairá, Canindeyú Department Venezuela La Guaira State La Guaira, its capital city
See also Guiara, a rodent