Abstract: The cement-based composite shielding material is made of cement and shielding mediums, which are industrial waste materials - steel scrap and iron sand. The effects of these shielding mediums on shielding properties and electric volume resistivity are studied. The results indicate that when the content of steel scrap increase, the shielding effectiveness and conductive properties of the steel scrap-cement composites are improved greatly. The shielding effectiveness of composites is shown up to 35.65 dB in 0.3-3GHz frequency range, and the resistivity of the conductive composites is only 34.43. In addition, the thickness of the composites has an obvious influence on its electromagnetic shielding effectiveness, when the thickness increase, the shielding effectiveness is improved obviously.