Eucalyptus microcorys is a tree that typically grows to a height of , occasionally to and forms a
lignotuber. It has rough, fibrous or stringy brownish bark on the trunk and branches. Young plants and
coppice regrowth have egg-shaped leaves that are paler on the lower surface, long and wide. Adult leaves are glossy green, paler on the lower surface, lance-shaped to egg-shaped or slightly curved, long and wide on a
petiole long. The leaf veins are prominent, well-spaced and at an angle greater than 45° to the leaf mid-rib. The flower buds are usually arranged at the ends of the branchlets, on a branched
peduncle in groups of seven or nine, the peduncle long, the individual buds on
pedicels long. Mature buds are club-shaped, yellow, long and about wide with a rounded
operculum. Flowering occurs between August and January and the flowers are white to lemon-yellow. The fruit is a woody conical
capsule long and wide with the valves near rim level. ==Taxonomy and naming==