The couple began dating in 2006 when they were paired together on the dance competition TV show "Dancing with the Stars."
"Karina has parted ways with her two-year relationship with Mario Lopez," Smirnoff's representative told People.com. "The relationship wasn't heading in the right direction."
"Karina and I have the utmost respect for each other. She is a phenomenal and talented woman. I support her always and feel blessed to have her in my life," Lopez said in a separate statement issued to People.com by his representative.