Berlin’s star animal attraction died aged four in March 2011 after he drowned in his enclosure following an inflammation on the brain.
Last February, Berlin’s Natural History Museum said it would make a model of Knut using the polar bear’s real fur – despite protests from animal rights activists and Knut fans.
And on Monday he was put out in a museum display case.
Born in Berlin Zoo in December 2006, Knut enjoyed worldwide fame and became a media darling.
After his mother rejected him he was kept alive by zookeepers feeding him with a bottle.
More than 11 million visitors saw Knut during his lifetime.
PHOTO GALLERY: Knut the polar bear
The museum hopes plenty more will now come through its doors for the exhibition, which includes a model coral reef and a stuffed baby gorilla.
"Our goal is to be the most exciting natural history museum in the world," said museum director Johannes Vogel.