The invention relates to a preparation method of 
dendrobium aurantiacum 
powder. The preparation method comprises the following steps of (1) performing cleaning treatment: removing leaves of fresh 
dendrobium aurantiacum, adding the 
dendrobium aurantiacum without leaves in cleaning liquid, performing soaking and cleaning, performing 
fishing out, and removing 
surface moisture for standby application;(2) performing 
drying: 
drying the dehydrated dendrobium aurantiacum until the 
water content is 60-70%, and performing 
cutting into slices; (3) performing freezing treatment: freezing the dendrobium aurantiacum slices; (4) performing 
differential pressure puffing treatment: performing 
differential pressure puffing on the frozen dendrobium aurantiacum slices, to prepare the puffed dendrobium aurantiacum slices; (5) performing low-temperature reflow extraction and concentration: adding an 
organic solvent to the puffed dendrobium aurantiacum slices, and performing low-temperature reflow extraction and concentration to prepare primary concentrate; (6) performing concentration: sending primary concentrate into a spherical vacuum concentrating tank, and performing concentration to prepare secondary concentrate; (7) performing 
drying and crushing: drying a secondary concentrated solution, and performing crushing, to prepare crude dendrobium aurantiacum 
powder; and (8) preparing components. According to the method provided by the invention, the bioactive components of the dendrobium aurantiacum are low in 
loss rate, high in dissolving and leaching efficiency and high in 
biology absorptionand 
utilization rate.