In recent years, photovoltaic industry has developed rapidly. Facing the situation of traditional energy resources exhaustion and continuing oil price rise, solar energy as a renewable clean energy has been the focus of world attention. In all kinds of solar battery, polysilicon solar cell is the most important. However, the high cost of polysilicon, which accounts for 50% of the total cost, hinders the development of photovoltaic industry. In this paper, for the purpose of reducing cost of polysilicon production, metallurgy methods, for example, chloridizing roasting has been applied for purification. A feasible technological route for polysilicon purifying was developed.