The Ilosaarirock Festival is an annual rock festival held on the second weekend of July in Joensuu, Eastern Finland. Founded in 1971, Ilosaarirock is the second oldest rock festival in Finland still active, and one of the oldest in Europe.

Ilosaarirock is an entity of events that in its entirety, with clubs and side-events, spans Friday to Sunday. The actual festival takes place on Saturday and Sunday. The festival site, called Laulurinne, stages performances on five separate stages with over 50 artists.

Ilosaarirock is organized mainly by volunteers and is put together by over 1,500 volunteer workers. The Ilosaarirock festival’s graphic look is chosen through an open design contest every year. The Ilosaarirock festival is organised by Joensuu Pop Musicians’ Association, which is a non-profit organisation. The profits of the festival are used to support the North Karelian music scene, bands and artists.