The invention provides a method for extracting camellia chrysantha polysaccharide from camellia chrysantha leaves. The method comprises the following steps: 1, adding water to the camellia chrysantha leaves for conducting extraction, and obtaining an aqueous extract solution; 2, after concentrating the aqueous extract solution, adding ethanol for conducting precipitation, and obtaining precipitate for standby application; 3, washing the precipitate obtained in step 2 with absolute ethyl alcohol and acetone in sequence, then adding distilled water for conducting dissolution, then adding protease for conducting enzymolysis, and obtaining enzymatic hydrolysate; 4, placing the enzymatic hydrolysate and conducting treatment for 10-60 seconds under ultrasonic waves with the frequency ranging from 1000 kHz to 5000 kHz, then conducting dialysis through a dialysis bag with the molecular cut off being 10000, obtaining reserved liquid for conducting dialysis through a dialysis bag with the molecular cut off being 500000, obtaining penetrating liquid for conducting concentration, adding ethanol for conducting precipitation again, and obtaining precipitate for standby application; 5, washing the precipitate obtained in step 4 with absolute ethyl alcohol and acetone in sequence, then adding distilled water for conducting dissolution, conducting activated carbon decoloration, filtration and drying, and obtaining the camellia chrysantha polysaccharide. The camellia chrysantha polysaccharide obtained through the method has high immunological competence.