Elachista canapennella is a moth of the Elachistidae family. It is found from Fennoscandia and northern Russia to the Pyrenees, Italy and Romania and from Ireland to central Russia. The wingspan is 8–10 millimetres (0.31–0.39 in). Adults are on wing from April to June and from July to September. There are two generations per year. The larvae feed on Agrostis stolonifera, Arrhenatherum elatius, Avenula pubescens, Deschampsia cespitosa, Festuca, Holcus mollis and Poa. They mine the leaves of their host. The pupation takes place outside the mine.