The yellow-rumped thornbill (Acanthiza chrysorrhoa) is a species of passerine bird from the genus Acanthiza. The genus was once placed in the family Pardalotidae but that family was split and it is now in the family Acanthizidae. There are four subspecies of yellow-rumped thornbill. It is a small, brownish bird with a distinctive yellow rump and thin dark bill. It inhabits savannah, scrub and forests across most of Australia and eats insects. The species engages in cooperative breeding.
The yellow-rumped thornbill is the largest species of thornbill. It has a short tail and a long slender bill. The species has a distinctive yellow rump, a black forehead with white spots, grey head and neck, a white line above the eye and white throat. The belly is white with light buff below the wings. The wings are grey and the tail is black. The plumage varies somewhat, depending on subspecies.