Now a day’s utilization of nano materials have been increased for enhancing the ultrahigh performance cementitious composites. Accordingly, graphene oxide (GO) was found as one of the nanomaterials, which represents an unprecedented range properties with a potential to enhance the strength and toughness of cement based composites. GO is also an appropriate material to react with binder particles as it consists a range of reactive oxygen operational chemical groups. This paper investigates the effect of graphene oxide (GO) on microstructure and strengthened properties of fly ash and silica fume based cement composites, by determining the characteristics of cement composites through mechanical and micro structural studies (SEM and XRD analysis). The Scanning Electron Microscope (SEM) images exhibited that, graphene oxide (GO) converted the structural nature of cement composite from a porous nature to a considerably pore filled nature with the improved mechanical properties. XRD technique was assisted in identifying the crystalline materials and studying the phase composition of cement composites. This significant extensive research provides a new pathway for achieving high performance cement composites.