The host started brightly as Patrick van Aanholt hit the post, while Andries Noppert denied Tobias Lauritsen. Just before the half hour mark, Mitchell van Bergen made it 1-0 with a close-range tap in.
Sparta remained in control and eventually, Lauritsen made it 2-0 with a penalty. Substitute Nokkvi Thorisson then added a third with an excellent strike.
Alireza Jahanbakhsh pulled one back with a penalty before the end but Sparta eased to victory and moved up to eighth.
Heerenveen sits in 9th place.