Chengjiang County 澂江县

Chengjiang County (Chinese: officially 澂江县; often spelled 澄江县; pinyin: Chéngjiāng Xiàn; earlier Tchinkiang) is in Yuxi, Yunnan Province, China, just north of Fuxian Lake.

In evolutionary biology, and especially paleontology, Chengjiang County is noted for soft-tissue fossil finds, of the Maotianshan Shales, dated to between 525 and 520 million years ago during the Cambrian explosion, which "are as spectacular as the Burgess Shale fauna, and significantly older." These fossils are considered one of the most important fossil finds of the 20th century. They contain an exquisite degree of detail, cover a diverse range of fauna, and are significant in attempts to understand the evolution of life on Earth.