Pääjärvi may refer to:

• Pääjärvi (Karstula), located in Karstula in the region of Keski-Suomi, Finland
• Pääjärvi (Lammi), located between the cities of Hämeenlinna and Hämeenkoski, Finland
• Lake Pyaozero (Finnish: Pääjärvi), located in the Republic of Karelia, Russia

• Pyaozersky, a settlement in the Republic of Karelia, Russia, called Pääjärvi in Finnish

• Magnus Pääjärvi (born 1991), Swedish ice hockey player

This disambiguation page lists articles associated with the title Pääjärvi.
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