The 41-year-old actress and 37-year-old Coldplay frontman have two children together -- Apple 10, and Moses, 8.
The couple released a statement via Paltrow's lifestyle website, Goop.
"It is with hearts full of sadness that we have decided to separate," the statement reads. "We have been working hard for well over a year, some of it together, some of it separated, to see what might have been possible between us, and we have come to the conclusion that while we love each other very much we will remain separate."
"We are, however, and always will be a family, and in many ways we are closer than we have ever been," they add. "We are parents first and foremost, to two incredibly wonderful children and we ask for their and our space and privacy to be respected at this difficult time. We have always conducted our relationship privately, and we hope that as we consciously uncouple and coparent, we will be able to continue in the same manner."