山栖木（学名：Orothamnus zeyheri）是分布在南非西开普省的一种山龙眼科植物。它们是直立及树枝稀疏的灌木，最高达5米。

山栖木极之稀有，且受到《濒危野生动植物种国际贸易公约》附录一的保护。它们的寿命很短，平均只有10年，最多也只是20年，很易被火烧毁。其种子可以在地底下35年仍能生存，奇怪的却是要靠火来发芽。其传播媒介不明。它们生长在海拔450-850米的泥媒沼泽。它们种子的发芽率很低，且受到开普敦沼鼠掠食；若周围的土壤被蹂躏，疫霉菌会令它们死亡。若成功将它们移植到风轮花的根茎，则可保存它们免至灭绝。

Orothamnus (Greek 'oros' mountain, 'thamnos' bush) or 'Marsh Rose' is a monotypic fynbos genus in the family Proteaceae occurring in the Kogelberg and Kleinrivier Mountains of Hottentots-Holland in the Western Cape Province of South Africa. It is an erect, sparsely branched shrub to 5 m tall and was first depicted by Jean Villet, a Capetonian artist and dealer in natural history specimens, in Curtis's Botanical Magazine 74: plate 4357 in 1848.