Abstract: The forest remains were unearthed at Chenghuang of Yehaizi in Mianning county, Sichuan Province. The specimens from the relict wood, fruits or cones, and leaves or needles have been identified, as well as the C¹⁴ age and the chemical and physical properties of wood determined. It follows from the results that the ancient forest, which existed in the area Yehaizi 6058±167 years ago, was a subtropical mixed forest composed of many coniferous and evergreen or deciduous broadleaved tree species. Also discussed are the burying and preservation of the forest and the survival of its remains, the succession of forest, and the changes in ecological environments.