Ancient environmental DNA(ancient eDNA)refers to ancient DNA(aDNA)derived from palaeoenvironmental samples. Different from ancient DNA, ancient eDNA contains a mixture of highly fragmented DNA from multiple organisms, and usually attached to humic acids and mineral particles. Ancient eDNA has been found to be preserved in coprolites, dental calculus, gut contents, ice, permafrost, and the sediments from lake, marine, cave and archaeological sites. Ancient eDNA technology started in 1998, and has experienced three stages of development:(1)identifying specific species through DNA barcodes, (2)recovery of certain groups of organisms via DNA metabarcoding, and (3) reconstruction of paleoecosystems using shotgun metagenomics. Compared to the fossil identification methods, the ancient eDNA methods have several advantages such as:less sample consumption, easier operation, no demand for fossils, and more species information revealed from one sample. Therefore, the ancient eDNA methods have been widely applied in many fields of environmental archaeology, including palaeoecological reconstruction, ancient human diet, ancient agricultural development, ancient human migrations, as well as anthropogenic environmental change. In this paper, we review the development, research methods, application directions and existing problems of ancient eDNA technology. We conclude that with the improvement of ancient eDNA technology, its application in environmental archaeology would be more promising.