Elachista fulgens is a moth of the Elachistidae family. It is found in Italy, Germany, the Netherlands and Japan (Kyûsyû, Ryûkyû; Honsyû). The length of the forewings is 2.4-2.7 mm for males and 2.6-3.5 mm for females. The forewings have a silvery spot just basally of the tornal spot. The larvae feed on Carex acutiformis, Carex elata and Carex riparia. They mine the leaves of their host plant.