In this study we explored the radiation properties of CO2-reacted Portland which take place in kiln process of cement production. The use of CO2 can change Portland density via chemical process to obtain CaCO3. When the CO2 capture rate of Portland cement is zero, the density is 2.3 g/cm3, while the CO2 capture rate is 100%, the density is reached to 2.705 g/cm3. The radiation shielding properties were explored using FLUKA code. To define the radiation shielding properties of the CO2-reacted Portland, four types of beams (photons, electrons, protons and neutrons) were used. These beams have been used to explain the leptonic and hadronic interactions. The CO2-reacted Portland radiation length and density have been calculated and presented. The energy depositions of four beams with various beam energies were examined by considering density variation of the cement. It has been found that CO2-reacted Portland has more efficient radiation shielding than traditional Portland materials. The carbonization of Portland will be carried out during the kiln process, not by the CO2 diffusion process, which is a very slow process, but by the faster and more convenient spray method.