A method for purifying tungsten hexafluoride of high purity, capable of producing tungsten hexafluoride of higher purity than that of the related art, readily and at a low cost. A method for purifying tungsten hexafluoride of high purity, characterized in that tungsten hexafluoride containing molybdenum hexafluoride as an impurity, makes contact with a layer, in which a metal or an alloy is packed, containing at least one of molybdenum, tungsten, copper, nickel, iron, cobalt, zinc, titanium, aluminum, calcium, and magnesium at a temperature ranging from 0.degree. C. to 100.degree. C.