Grevillea phillipsiana is a prickly, spreading to erect shrub that typically grows to a height of and has linear or tapering leaves, long and wide. The edges of the leaves are rolled under enclosing most of the lower surface and the upper surface has ridges along its length. The flowers are usually arranged on the ends of branches in clusters of 2 to 14 on a silky-hairy rachis long. The flowers are red, the pistil long. Flowering occurs from July to September and the fruit is a narrowly oval follicle about long.