The invention discloses flake silver powder prepared by means of a chemical reduction method and a preparation method thereof. The method comprises the steps that firstly, all raw materials are selected and weighed; secondly, under constant-temperature water bath conditions, gum acacia powder, potassium sulphate, hydrogen peroxide and vitamin C are added into water and stirred to dissolve, and thepH value of a solution is adjusted; thirdly, silver nitrate is added into water and stirred to dissolve, and the pH value of a solution is adjusted; fourthly, the silver nitrate solution is added into the reducing solution for reaction, and stirring and heat preservation are performed; and fifthly, after flake silver powder particles are formed, cooling and filtering are performed in sequence, the particles are cleaned with pure water and then cleaned with ethyl alcohol, finally, extraction filtration is performed to remove moisture, and drying is performed. The invention further provides theflake silver powder prepared by means of the method. The preparation method is used for preparing the flake silver powder with the grain size being around 2-4 [mu]m, and the silver powder is high incrystallinity degree, good in dispersity, high in shape and grain size uniformity, stable in performance, excellent in quality, simple in preparation method, low in cost and high in yield.