Badr Hari announced on Monday that he has tested positive for the corona virus.
His fight with Benjamin Adegbuyi in early November has been postponed by kickboxing association GLORY.
"I am currently in home quarantine and am recovering well after a few days of illness. I need rest at this point and will resume training as soon as possible," Hari wrote in an Instagram post on Monday.
"We have taken all the necessary precautions from the start, but unfortunately that did not prevent this positive test. It also shows how seriously we have to take the virus."
The 35-year-old Hari would compete in the heavyweight against Adegbuyi on November 7.
He headlined GLORY 76, but the entire event is now being postponed.
It is not yet known when the fight between Hari and Adegbuyi can be caught up.
"It sucks because Badr, his trainers and his environment have done everything they can to prevent contamination," said GLORY Vice President Scott Rudmann.
"He was in full training on his way to the ring. His health and recovery are of course the most important."