Rhoicissus rhomboidea is an evergreen, strong climber to small tree that grows from 3 to 6 m in height. The dark green leaves are tri-foliate (comprising of 3 leaflets); leaflets are asymmetrical, with short stalks; leathery and glossy with pale russet hairs underneath and with an irregularly toothed margin. Each tooth is tipped with an approximately 1 mm long point, and the leaflet apex tapers to a point. The usually dark brown stem is multi-branched, with very strong tendrils. The tendrils are forked. 

The flowers are small and greenish yellow, in branched heads in the leaf axils (the angle between the upper side of the stem and a leaf, branch, or petiole), in spring to midsummer (between September and January). Edible grape-like fruits appear in clusters after flowering, in late summer to autumn (from January to April) and may continue to late spring (October), maturing to a dark red to purple colour.