GUA3E project has been launched in 2018 by the National Park of Guadeloupe in partnership with the private company SPYGEN. Two independent consultants have been involved from the early stage of the project. The project is funded by the Euro-pean Regional Development Fund, the two partners and the water agency of Gua-deloupe. The environmental DNA (eDNA) metabarcoding is an innovative technology based on searching for traces of DNA in the environment (water, soil, biofilm…) enable the monitoring of key taxonomic groups. This technology has been successfully implemented in French Hexagon since 2011, in aquatic ecosystems, where it’s a relevant method of the monitoring of rare or secretive species, including fish, crus-taceans, amphibians, mammals or bivalves. Thanks to its ease of implementation, the method can also be used to reinforce ecological surveillance operations. Guadeloupe is well known for its extraordinary biodiversity but also for the numer-ous threats that weight upon it, such as exotic and invasive species. Environmental conditions are roughly different in Guadeloupe compared to French Hexagon (short and turbulent streams, intense UV radiation, oligotrophic waters, high temperature and relative abundance of crustaceans). . The aim of the GUADE project was thus to test the eDNA metabarcoding method for the inventory of fish and crustaceans in Guadeloupe and compare the results with the traditional method of species inven-tory: the electric fishing. The second aim of the project was to create a reliable reference data base for local species’ sequences for these two taxonomic groups, which is a critical factor of the quality of the results. Two campaigns were conducted in February and July 2019. Eighteen sites (located on nine rivers) were studied. On each site, electric fishing and eDNA sampling (3 replicates) were performed. The samples were sent to Spygen laboratories where they were analyzed. The results of the first campaign are displayed. They show a good correlation be-tween the inventories obtained by the two methods, meaning eDNA method could be successfully implemented in Guadeloupe.