The Titanic hunk was first linked to Heatherton in December, 2011, but they recently called time on their romance due to their conflicting work commitments, according to Us Weekly magazine.
A source tells the publication, "They split a few weeks ago. There's no bad blood - they still care about each other a lot.
"They're both just really busy; they had crazy schedules."
DiCaprio has been shooting the new Martin Scorsese movie The Wolf of Wall Street in New York of late after spending much of 2012 filming The Great Gatsby in Australia and Django Unchained in New Orleans, Louisiana.
It's the actor's latest failed model romance - he previously dated Gisele Bundchen and Bar Refaeli, and enjoyed a fleeting romance with actress Blake Lively last year. The Gossip Girl beauty has since wed actor Ryan Reynolds.