The invention discloses a preparation method of a polysaccharide-silk fibroin composite anticoagulant biomaterial. According to the process, the polysaccharide-silk fibroin composite anticoagulant biomaterial is prepared from raw materials of corn starch, Arabic gum, mannan, polyethylene carbonate, polycarbonate, silk fibroin, polydimethylsilane, triethyl phosphate, ethambutol, methane sulfonic acid and the like respectively by the steps of ultrasonic oscillation dispersion, sieving sorting, vacuum heating reaction, injection molding die-pressing, cooling fixing, ultrasonic cleaning, absorption equilibrium of an aqueous solution of positive and negative polyelectrolytes, washing and air-drying, nitrogen protection curing and the like. The prepared polysaccharide-silk fibroin composite anticoagulant biomaterial is low in raw material cost, has obvious anticoagulation and antithrombotic activity, and is suitable for application in the aspect of various medical blood pipes and accessories.