Reps for the couple told People magazine that the split was amicable.
"Diane Kruger and Josh Jackson have decided to separate and remain friends," the representatives said in a statement.
Jackson, 38, and Kruger, 40, began dating in 2006, after her marriage to French actor Guillaume Canet ended. She once told Town & Country magazine that she decided at that point in her life to make "different choices."
"Meeting someone like my partner, who has a very different perspective, who likes to travel in a different way and be open to various experiences was so important," she said of Jackson. "I was 30 years old and I was already bored of fancy hotels."
Earlier this year, Kruger moved to New York City to be with Jackson. They reportedly also own homes in Paris and Vancouver.
"I just moved this week. I need to unpack and buy some house stuff, like candles and books," she told Net-a-Porter's The Edit in March. "[Moving here] was a major commitment. That's a big step into adulthood for me, to allow that time for someone else out of my time."
A rep for the couple did not immediately respond to ABC News' request for comment.