"Whoever has the baby polar bear lantern won't be able to display it without being noticed, because it really is one of a kind.
"You're not going to get in trouble, we just want the bear back."
The bear was made in Zigong in China and has been a part of the festival since 2012.
"It would be sad for the mother bear to have to go on display by herself in the future," Ms King said.
It could be dangerous to plug the lantern in at home, Ms King said.
It is the second time in the festival's 17-year history that a lantern has been stolen.
A pink flamingo was stolen from the Christchurch Lantern Festival in 2005 but was later returned to a radio station after a public appeal.
The China on Ice display was created to symbolise China's work in Antarctica and the Arctic.
China operates two year-round stations in west and east Antarctica, plus its inland summer station Kunlun located on Dome A, the highest spot in Antarctica.
China has also had a research station in the Arctic since 2004.
• If you know the bear's whereabouts, contact the Asia NZ Foundation on (09) 369 5014. A collection point can be arranged.