The long-eared owl is a medium-sized owl, 31–40 cm in length with an 86–100 cm wingspan and a body mass of 178–435 g . It has erect blackish ear-tufts, which are positioned in the centre of the head. The ear-tufts are used to make the owl appear larger to other owls while perched. The female is larger in size and darker in colouration than the male. The long-eared owl's brownish feathers are vertically streaked. Tarsus and toes are entirely feathered. Eye disks are also characteristic in this species.