Zohn, 38, and Morasca, 32, met after she won "Survivor: Amazon" and he was crowned champion of "Survivor: Africa." They subsequently competed together on "The Amazing Race" and headlined their own show, "Everyday Health."
Zohn recently underwent successful treatment for Hodgkins lymphoma.
"It is with much consideration and a heavy heart that we are announcing that after 10 years of a loving relationship, the decision was made to move on without each other," the couple said in an exclusive statement to People.com Monday.
"We will carry with us the memories of a relationship grounded in love, laughter, support and friendship," the statement said.
"We have experienced some of life's greatest joys and toughest challenges together and our decision to be apart can never diminish that. We want to thank everyone for their support and we ask that our privacy be respected as we move forward."