Ranua is a municipality of Finland.
The municipality has a population of 4,259 (30 September 2012) and covers an area of 3,694.82 square kilometers (1,426.58 sq mi) of which 241.09 km2 (93.09 sq mi) is water. The population density is 1.23 inhabitants per square kilometer (3.2 /sq mi).
The municipality is unilingual Finnish. The best known attraction is Ranua Zoo, a wildlife park of arctic animal species which is the northernmost zoo in the world