Hakea oldfieldii is an open, straggling shrub with upright branches and growing to a height of. The smooth, needle-shaped leaves are more or less long and wide and grow alternately. The rigid dark green leaves may be curving or straight and end in a sharp point. The branchlets are smooth and covered with a bluish green powdery film. The inflorescence consists of 8–20 white or cream-yellow flowers in a raceme in the leaf axils on a smooth stalk long. The flowers appear in profusion and have an unpleasant scent. The over-lapping flower bracts are long, the pedicel long. The smooth, cream-white perianth long and the pistil long. The fruit are egg-shaped almost rounded, long, wide with an uneven surface, occasionally warty ending with two prominent horns about long. Flowering occurs from August to October.