Alajärvi

Alajärvi
Town
Alajärven kaupunki
Alajärvi stad
Alajärvi Church
Location of Alajärvi in Finland
Interactive map of Alajärvi
Coordinates: 63°00′N 023°49′E / 63.000°N 23.817°E / 63.000; 23.817
Country Finland
RegionSouth Ostrobothnia
Sub-regionJärviseutu
Charter1869
Town privileges1986
Government
 • Town managerVesa Koivunen
Area
 (2018-01-01)
 • Total
1,056.74 km2 (408.01 sq mi)
 • Land1,008.77 km2 (389.49 sq mi)
 • Water47.99 km2 (18.53 sq mi)
 • Rank78th largest in Finland
Population
 (2025-06-30)
 • Total
9,065
 • Rank106th largest in Finland
 • Density8.99/km2 (23.3/sq mi)
Population by native language
 • Finnish94.9% (official)
 • Swedish0.1%
 • Others5%
Population by age
 • 0 to 1417.4%
 • 15 to 6454.3%
 • 65 or older28.3%
Time zoneUTC+02:00 (EET)
 • Summer (DST)UTC+03:00 (EEST)
Websitealajarvi.fi

Alajärvi (Finnish pronunciation: [ˈɑlɑˌjærʋi]; lit.'lower lake') is a town and municipality of Finland. It is located in the South Ostrobothnia region. The town has a population of 9,065 (30 June 2025) and covers an area of 1,056.74 square kilometres (408.01 sq mi) of which 47.99 km2 (18.53 sq mi) is water. The population density is 8.99 inhabitants per square kilometre (23.3/sq mi). The town is unilingually Finnish.

The municipality of Lehtimäki was consolidated with Alajärvi on 1 January 2009.