The invention relates to a method for synthesizing an intermediate of Apixaban comprising reacting a compound of formula I with 5-chloro-valeryl chloride in the presence of inorganic base in an inert solvent to obtain a compound of formula II, with the reaction formula of (A), wherein R is selected from nitro group and the group (B). The method is mild in reaction condition, simple in operation, easy in purification, inexpensive in production cost, environmental-friendly, and suitable for industrial production.