It is a mounded to almost prostrate shrub with divided leaves, the end lobes triangular, and usually down-curved, more or less toothbrush-like clusters of cream-coloured flowers that turn` pink to red after opening.

Grevillea pachylostyla is a mounded to almost prostrate shrub that typically grows to a height of up to 1.5 m (4 ft 11 in), its branchlets silky- or woolly-hairy.

The flowers are cream-coloured at first, but soon turn pink then red with a black base, the pistil 16–18.5 mm (0.63–0.73 in) long.

pachylostyla in his book New Names in Grevillea (Proteaceae) from specimens collected by James Hamlyn Willis in 1964.

[8] Grevillea pachylostyla grows on rocky granite outcrops near streams in the upper catchment of the Buchan River in north-eastern Victoria.