"Prince Christian has subsequently tested positive for COVID-19."
The Palace confirmed Christian is now in isolation in Frederik VIII's Palace at Amalienborg.
It also confirmed he has not been in contact with any other members of the royal family aside from his mother, father and siblings.
It is understood the Crown Prince family will remain in isolation until it is ultimately deemed safe, especially given Frederik's mother, Queen Margrethe II is 80 and falls in the high risk category.
The family have made numerous changes to their schedules this year - back in March, after two months studying abroad in Switzerland, Princess Mary accompanied her children home to Denmark to go into isolation.
They have largely remained there ever since.
A Palace spokeswoman, Lene Balleby said in a statement that no other members of the family had tested positive to COVID-19, but they would remain at their home in Copenhagen until the 14-day mandatory quarantine period was up.
"In connection with the test response, the Royal House has received advice from the Danish Agency for Patient Safety regarding infection detection and testing of the Crown Prince's family," she said.
"In the coming days, the family will stay in isolation in Frederik VIII's Palace, until it is safe to break the isolation again according to the current guidelines".
This story originally appeared on our sister site Now To Love