Somerhalder and Dobrev, who play Elena Gilbert and Damon Salvatore on the hit TV series, have mutually decided to end their relationship, reported Us magazine.
The two actors went public with their romance in 2011 and have reportedly vowed to remain friends and not let the split affect their work on the supernatural drama.
"They are consummate professionals and will continue to work together and remain best friends, which is where the relationship started," a source said.