A polysilicon purification method includes the following steps: impurity containing low purity polysilicon is maintained to be fusion state for a period of time in a crucible; the polysilicon liquid in fusion state is gradually cooled and solidified from the bottom to the top through relative move of the crucible and an induction coil arranged at the periphery of the crucible in a surrounding way; and the solidified polysilicon after cooling is taken out from the crucible and is purified by mechanical cutting. The invention also discloses a crucible used for polysilicon purification and a purification device provided with the crucible. The invention has the advantages that the polysilicon purification method and device has strong operability, low cost, no secondary pollution in purification process and the like.