Brachychiton chrysocarpus Cowie & Guymer from Fish River Station in the north-western part of the Northern Territory is described as a new species. It is compared with B. tuberculatus Guymer and B. xanthophyllus Guymer, but differs especially in the softer finer indumentum, shorter caducous stipules, slender paniculate, open inflorescence, the weakly tuberculate follicles and other characters. It appears to be restricted to Eucalyptus tectifica woodland on slopes of ∼17° associated with ferruginous sandstone of the Waterbag Creek formation. Its conservation status is discussed and assessed.