Abstract: At Beijing HI-13 Tandem Accelerator the high intensive sputter source is used to extracting ion beam, but there are some kinds of beam impurities. After detailed analysis it is found that the beam impurities are caused by inside source insulation bushing. The inner structure of the source was improved with metal shields fixed inside and outside of the insulation bushing between the cathode and the anode. After the improvement, beam impurities from the intensive sputter source decrease and the purity and intensity of the needed beams increase.