The Titanic star is said to have made the decision because he felt that Refaeli wanted to get too serious too quickly, People reports.
A source said: "They're taking time off for the time being, they've split. It could just end up as a break but for now they're doing their own thing."
Another added: "She wanted to move faster than he did, she wanted to move in together so he broke it off."
Earlier this year, a friend of DiCaprio confirmed that the couple were not engaged despite media reports.