The televised crushing in Dongguan city, in the Guangdong province, is being attended by the media, diplomats and conservationists. The ivory stash includes carvings, ornaments and tusks confiscated over the years.
State media said the move was to "discourage illegal ivory trade, protect wildlife and raise public awareness." Some powder from the crushed ivory will be disposed, and the rest will be preserved in a museum.
Trading in ivory was banned in 1989, but high demand from Asian countries including China is thought to have spurred the poaching of elephants in sub-Saharan Africa.
In a similar move, the U.S. Fish and Wildlife Services recently crushed nearly six tons of African and Asian elephant ivory.