The brush-tailed phascogale was first described by Friedrich Meyer in 1793; George Shaw published a revised description in 1800.

Its tail is covered with long black hairs on the lower half that can erect, causing it to appear similar to a bottle brush.

Males, which can reach up to 310 grams (11 oz), are larger than females, normally weighing less than 210 g.[8] The brush-tailed phascogale has a widespread but fragmented distribution throughout all states of Australia, excluding Tasmania.

As a result of habitat destruction and predation by the red fox and feral cat, they are believed to have disappeared from roughly half of their former range.

All male brush-tailed phascogales die before reaching one year of age, generally from stress-related diseases brought about by the energy expended in a bout of frenzied mating.