Abstract: Environmental DNA（eDNA）refers to the sum of DNA fragments of different species extracted directly from the living environment of organisms,and eDNA is becoming more and more popular in the study of fish resources. It is a novel investigation approach for biological resources,i.e.,whether or not existence of fish species in a water environment can be determined,based on the identification of specific gene fragments of fish and by aligning with the identification fragments obtained via molecular methods to detect eDNA. Compared with traditional methods,eDNA technology has the advantages of high sensitivity,low cost,and no damage. It can quickly detect invasive species,endangered species,and rare species. However,there are some deficiencies for it,for instance,the real-time data whether target species exist or not cannot be acquired,biological characteristics such as the growth stages of species as well as population structure cannot be obtained,“purebreds” cannot be distinguished from hybrids. The eDNA technology is of subversive significance to the study of fish resources and shows a good momentum of development. This article mainly reviews the application of eDNA technology in the research of fish species diversity,resource estimation and population distribution,aiming at providing some ideas for the study of fishery resources. It can be expected that the combination of eDNA technology and traditional survey methods will become a development trend for fish resources research.

Key words: environmental DNA, eDNA technology, fish resources