Pyhäjärvi (1993–1995 Pyhäsalmi) is a town and municipality in the south of Northern Ostrobothnia region, Finland.

Neighbouring municipalities are Haapajärvi, Kiuruvesi, Kärsämäki, Pielavesi, Pihtipudas and Pyhäntä.

The town has 4,709 inhabitants (31 December 2024),[2] of whom some 60 percent live in the two population centres Pyhäsalmi and Ruotanen.

It is the second smallest town of Finland in term of population after Kaskinen in the Ostrobothnia region.

[8] The mine facilities and the associated infrastructure will be used for underground business and research under the Callio Pyhäsalmi project.