The Sedge Wren is a small (9-15 cm, 7-10 g), insectivorous, grassland specialist passerine. The bill is rather short, slightly curved, with gray upper mandible and paler lower mandible. Head gray-brown streaked with white and pale buff supercilium. Body grey-brown with streaked black and white, with throat and belly whitish with cinnamon on sides and undertail. Rounded wings with rather long tail barred with black. Sexes are similar in plumage, being males little larger in some measurements.