The morphology of the modified Portland cement hydration products was studied transmission electron microscopy. The combined effect of polyvinyl alcohol (PVA) and sucrose on the morphology of hydrosilicates nanoparticles has a synergistic character. he presence of PVA enhances the effect of sucrose. The effect of synergism must be considered in the preparation of multicomponent modifier compositions including PVA

Keywords: "modified cement stone, transmission electron microscopy, the morphology of nanoparticles of hydrosilicates, sucrose, PVA, synergistic effect. "