Drymus brunneus is a species of dirt-colored seed bug in the family Rhyparochromidae found in the Palearctic.

[1] In the West Palearctic it is lacking only in the far north of Northern and Eastern Europe.

Habitats include shady deciduous and coniferous forests, lowland forests and occasionally more open habitats such as bogs and wet meadows.

Drymus brunneus lives hidden in damp, soil litter with fungus and moss.

They suck at seeds of various herbaceous plants and trees, such as Birch (Betula) and Alder (Alnus).