Darwinia biflora is an erect or spreading shrub to 80 cm high (family Myrtaceae) that is found in the northern and north-western Sydney suburbs, in the area bounded by Maroota, Kellyville, Cowan and North Ryde, within Baulkham Hills, Hornsby, Ku-Ring-Gai and Ryde local government areas.
D. biflora occurs on the edges of shale-capped ridges which are also areas favoured for development. Much of the habitat of this species has been cleared for urban growth, and many current sites are at risk from further clearing and urban expansion. Only 21% of sites are within national parks. The remainder are on a variety of tenures including lands owned or managed by Councils, the Department of Lands, the Roads and Traffic Authority or in private ownership.
The major threats to the survival of D. biflora arise from human interference in the environment. These threats range from loss of habitat through changes in land use and urban expansion, and degradation of habitat through the implementation of inappropriate fire regimes, slashing for easement maintenance, illegal track creation and weed invasion.