Rhododendron simsii (杜鵑) is a rhododendronspecies native to East Asia, where it grows at altitudes of 500–2700 meters. It is a shrub that grows to 2 m in height, with leaves that are ovate, elliptic-ovate or obovate to oblanceolate, 1.5–5 by 0.5–3 cm in size. Flowers range from white to dark red.
The species is common in Hong Kong. It is also distributed in Areas south of Yangtze in China as well as in Vietnam and Thailand.
Its specific name commemorates John Sims (1749-1831) who was the first editor of "Magazine Botanique".