Elsewhere, Vitesse Arnhem stay in trouble near the relegation zone as they went down 1-0 at RKC Waalwijk, and NEC Nijmegen enjoyed an away win at Twente.
Arvid Smit gave home side De Graafschap the lead at De Vijverberg, but that only managed to sting the visitors into life, and they drew level six minutes before the break through Romano Denneboom.
Heerenveen took control in the second period and John de Jong put them ahead a minute after the restart and former Sheffield Wednesday man Gerald Sibon stretched their lead three minutes later.
Denneboom got his second, and his side's fourth, just after the hour mark and Stefan Selakovic wrapped up the impressive victory in the final minute.
Vitesse Arnhem were looking to drag themselves away from trouble when they made the trip to Waalwijk but RKC came out on top thanks to a single goal from Patrick van Diemen.
Danny Hesp struck from the penalty spot after 19 minutes of NEC Nijmegen's game at Twente, and Youssouf Hersi doubled the lead after 34 minutes.
Sjaak Polak pulled a goal back for Twente after 78 minutes but it was not enough and the visitors held out for a 2-1 win.
Click below for match summaries:
De Graafschap v Heerenveen
RKC Waalwijk v Vitesse Arnhem
Twente v NEC Nijmegen
