天麻属（学名：Gastrodia），又名赤箭属，是兰科下的一个属，为腐生兰。该属共有约20种，分布于东亚、马来西亚至大洋洲。

Gastrodia is a genus of achlorophyllous orchid with 61 currently accepted species (as of June 2014). They are native to Asia (China, the Russian Far East, Japan, Korea, Southeast Asia, the Indian Subcontinent), Australia, New Zealand, central Africa, and various islands of the Indian and Pacific Oceans.