Ilmoilanselkä is a lake in Finland. It is part of a chain of lakes that begins from the lakes Lummene and Vesijako at the drainage divide between the Kokemäenjoki and Kymijoki basins, flows westwards from there through the lakes Kuohijärvi, Kukkia, Iso-Roine, Hauhonselkä and Ilmoilanselkä and drains into lake Mallasvesi.