Pediasia contaminella is a species of moth in the Crambidae family. It is found in almost all of Europe, Asia Minor, the Caucasus, Transcaucasia, Iraq, Iran, the Kopet Dagh and Minussinsk. The wingspan is 17–19 mm. Adults are on wing in July and August. The larvae feed on Poa species (including Poa maritima and Poa borreri) and Festuca ovina. They live in a silken tube.