Fontanesia is a genus of flowering plants in the family Oleaceae, usually treated as comprising a single species Fontanesia philliraeoides, though some authors split this into two species (see below). It is native to southern Europe (Sicily), southwestern Asia (Lebanon, Syria, Turkey) and eastern Asia (China), with two well-separated populations.
It is a deciduous shrub growing to 8 m tall. The leaves are opposite, lanceolate to narrow ovate, 3–12 cm long and 8–26 mm broad, with an acute apex and a usually entire margin, sometimes finely serrated. The flowers are white, with a deeply four-lobed corolla; they are produced in panicles 2–6 cm long. The fruit is a flat samara, surrounded by a wing.
There are two subspecies, often treated in the past as separate species. Despite the distance separating the two, the differences between them are minimal; the leaves of subsp. philliraeoides are sometimes cited as having finely serrated margins, but this character is not reliable.
The species name is often erroneously cited as "phillyreoides".