The invention discloses a method and device for increasing the impurity removal amount of volatile impurities in an electron beam smelting process. According to the invention, in an electron beam smelting process, the surface of a silicon melt can be fluctuated by changing the melting mode of an electron beam, so that the evaporation surface area is increased, the evaporation surface area of a melt interface is increased, and the evaporation amount of impurities in unit time is increased; a graphite substrate is placed at the bottom of a smelting crucible, and then the temperature distributionat the bottom of the silicon melt is changed, so that flowing of the silicon melt at the bottom of the smelting crucible is promoted, convection occurs in the silicon melt, and then melt exchange between the silicon melt at the bottom and the silicon melt at the top is accelerated. Through the change of the melting mode and the experimental device of the electron beam, the evaporation surface area of the melt is increased, the evaporation amount of the impurities in unit time is increased, and therefore, the problems that a silicon melt is low in impurity evaporation amount, long in melting time, large in silicon material loss and high in cost in an impurity removal process of volatile impurities are solved.