Ethmia mulleri is a moth in the Depressariidae family. It is found in Mexico. The length of the forewings is 9.7-10.4 mm. The ground color of the forewings is white, although the costal area above the cell is gray-brown, ending before the apex. The ground color of the hindwings is pale brownish, but darker under the costal brush. Adults are on wing in May, July, August and September.