The　mechanical　behavior　of　graphene　oxide　(GO)　reinforced　polypropylene　(PP)　fibers　cement-based　composites　was　investigated　by　three-point　bending,　microscratch,　and　nanoindentation　tests　at　macro,　micro,　and　nano　levels,　respectively.　The　microstructures　of　the　composites　with　GO-reinforced　PP　fibers　were　analyzed　using　SEM,　EDS,　and　XRD.　Both　nanoindentation　and　microscratch　tests　were　utilized　to　investigate　the　phase　transformations　in　the　cement　matrix　after　adding　GO.　It　was　found　that　adding　0.03　wt%　GO　most　effectively　improved　the　mechanical　properties　of　PP　fibers　cement-based　composites　best,　and　improving　their　strength　and　crack　resistance　of　composites.　In　addition,　statistical　nanoindentation　and　microscratch　techniques　showed　that　GO　could　promoted　the　hydration　of　cement,　and　greatly　increased　the　mechanical　strength　of　hydrated　calcium　silicate.