The invention relates to a process for extracting sweet potato 
protein by a 
thermal deposition method. The process is characterized by comprising the following steps of: treating 
cell sap to extract the sweet potato 
protein from the 
cell sap while producing sweet 
potato starch, separating and purifying by using a disc separator according to the difference of 
specific gravity of the 
protein and other substances such as 
starch and the like, removing fine fibers according to the 
solubility of the protein and the size of particles, and further purifying; purifying, concentrating, and degeneratingthe sweet potato protein to generate floccules according to the characteristic that the protein is degenerated at high temperature by a physical heating method; and concentrating, squeezing for dehydrating, 
drying, sieving, and performing aftertreatment to obtain a sweet potato protein commodity. The invention has the advantages that: (1) the sweet potato protein is degenerated by a steam jet 
cell sap heater, a moving part is not provided, and 
continuous production is ensured; (2) chemicals such as a flocculating agent and the like are not added, so that 
pollution is avoided, and subsequent treatment difficulty is reduced; and (3) the process is technically mature, and the industrial production capacity can be achieved.