The invention discloses an application of nervonic acid in preparing an anticoagulant drug for treatment. An animal model of qi stagnation and blood stasis in a rat is established by subcutaneous injection of epinephrine, and the rat is intragastric filled with nervonic acid, so that the effects of the drug on blood coagulation time, whole blood viscosity and plasma viscosity of the rat with tailamputation are investigated. The results show that the nervonic acid can prolong the bleeding time of tail amputation and shows dose dependence; and meanwhile, the nervonic acid can further reduce thewhole blood viscosity and plasma viscosity in the rat, which argues that the nervonic acid can improve the hemorheological state of the animal model of qi stagnation and blood stasis to play an anticoagulant role.