The Amisan Formation (Korean: 아미산층) is an Late Triassic geologic formation in South Korea.

Fossil records from this formation include plants, insects, and fish remains.

It is subdivided into five zones based on its lithology, lower sandstone, lower shale, middle sandstone, middle shale, and upper sandstone zones.

Depositional environments of the lower and middle shale zones of the Amisan Formation are thought to be lacustrine settings.

[4][5][6] Most of the fossils from the Amisan Formation are from the lower shale zone and the middle shale zone.