The invention discloses a method for synthesizing chiral five-membered carbon ring purine nucleoside through [3+2] cycloaddition based on allenoates and belongs to the field of asymmetric synthesis inorganic chemistry. The method takes alpha-purine substituted acrylate 1 and allenoates 2 as raw materials, and chiral STICP as a catalyst; after the raw materials and the catalyst react, chiral five-membered carbon ring nucleoside 3 is obtained; reaction has good enantioselectivity and has moderate to excellent yield. Chiral five-membered carbon ring nucleoside 3 is reduced under the condition ofsodium borohydride to obtain mono-alcohol five-membered carbon ring purine nucleoside 4; then mono-alcohol five-membered carbon ring purine nucleoside 4 is reduced by adopting DIBAL-H to obtain diolfive-membered carbon ring purine nucleoside 5.