The authors have estimated the effect of advanced superplasticizers of types Muraplast, Reamin, Weiss SM, Polyplast SP-1 and Melflux on radiation changes in Portland cement stone and concretes of radiation protection, based on experimental data from available literature, about the effect of such superplasticizers on thermal changes of Portland cement stone and the known analogy between thermal and radiation changes in Portland cement stone exposed to neutrons. The estimate of radiation changes in volume and compression strength of Portland cement stone used proposed ratios between the effect of superplasticizers on thermal and radiation changes in Portland cement stone, obtained through processing the published experimental results about the effect of superplasticizers S-3 and S-4 on radiation and thermal changes in Portland cement stone. Radiation changes in volume, crack formation, compression strength and deformation modulus of concretes, were measured with developed and tested methods for analysis of radiation changes in concretes based on information on changes of their components (aggregates and Portland cement stone). It has been established that advanced superplasticizers generally diminish radiation changes in Portland cement stone and concretes. The authors have demonstrated the extent by which such changes are reduced depending on various factors. It has been found that the effect of superplasticizers is in inverse proportion to the water-to-cement ratio of the mix as cement stone is made, by increasing the content of superplasticizer in the mix (for water reducing), and it depends on the fluency of fast neutrons.