The Ooldea dunnart (Sminthopsis ooldea), also called Troughton's dunnart after the person who found the species, is an Australian marsupial similar to the hairy-footed dunnart. It is greyish-yellow on its upper body and white on the underside with dark patches on its crown, forehead and in front of the eyes, and a pink thinly furred carrot-shaped tail. Its total length is ; its average body length is with a tail of . Its ear length is . It weighs between .
The Ooldea dunnart is found from the Tanami Desert in the Northern Territory, south to Ooldea in South Australia and east to neighbouring areas of Western Australia. The type of habitat it inhabits includes arid eucalypt and acacia woodlands, heathlands mallee scrub and hummock grasslands, low shrubland, open scrub and tall open shrubland.
The Ooldea dunnart has eight young between September and November but, since the species is not much studied, not much more is known. It is nocturnal and has been found in burrows and hollow logs.
It is believed, from evidence gathered, that this species eats insects.