Pimelea rupestris is a shrub that typically grows to a height of and has hairy young stems, the hairs pressed against the stem. The leaves are arranged alternately along the stems, elliptic to egg-shaped with the narrower end towards the base, long and wide, on a
petiole long. The upper surface of the leaves is more or less
glabrous and the lower surface sparsely hairy. The flowers are borne in leaf axils in heads of 40 to 80 on a
peduncle up to long, each flower on a
pedicel long. All the flowers on a plant are either all male or all female, the
floral tube long and white, the
sepal lobes long and densely hairy on the outside. Flowering has been observed from January to March and in September. ==Taxonomy==