The invention discloses a method for removing phosphorus, arsenic and boron in heavily doped silicon and a device thereof. The method comprises the steps of heating to melt dish bottom materials, initial and remaining materials, leftover materials and fragments of waste heavily doped silicon in semiconductor industry at a high temperature, and introducing an inert gas He, Ne or Ar into the meltedsilicon to promote evaporation by blowing and bubbling to reduce the concentrations of phosphorus, arsenic and boron doped in silicon, so that the semiconductor heavily doped silicon can be used as araw material of solar energy silicon. The inventive method arranges a blowing and bubbling device and a sampling spoon on a common Czochralski-silicon single crystal furnace, and controls the evaporation temperature and the blowing and bubbling time to realize effective control and random detection of impurities in silicon. When the total concentration of N-type impurities is less than 5*10<16>atms/cm<3> or the total concentration of P-type impurities is less than 1*10<17>atms/cm<3> and the corresponding specific resistance is larger than 0.1 omega.cm, the waste of the semiconductor heavily doped silicon can be used as the raw material for preparing solar energy silicon. The inventive method has the advantages of simple process and convenient operation; and can realize cyclic utilization of waste silicon.