Shanghai customs on Sunday announced they seized more than 2,000 endangered turtles in November 2015.
Customs officials said they found large numbers of live turtles hidden in six containers of crabs imported from Indonesia on November 19, last year, Xinhua news agency reported.
The containers were owned by a Shanghai company.
Most of the turtles were endangered species including amboina box turtle, pig-nosed turtle and spotted pond turtle.
The turtles were now in the care of local zoos, officials said.
The customs did not give more details, saying the investigation was still underway.
Environmentalists have warned that China's rising market for rare and exotic pets, such as turtles and snakes, has given an impetus to smuggling in these species.