It is part of the Kainuu region. The municipality has a population of 1,164 (31 December 2023), which make it the smallest municipality in Kainuu in terms of population. It covers an area of 897.93 square kilometres (346.69 sq mi) of which 62.31 km (24.06 sq mi) is water. The population density is 1.39 inhabitants per square kilometre (3.6/sq mi). The municipality is unilingually Finnish.

People born in Ristijärvi

• Salomo Pulkkinen, Member of Parliament
• Kari Härkönen, cross country skier
• Hannu Takkula, Member of the European Parliament
• Kaisa Mäkäräinen, biathlete