Different　dosage　of　TPEG-polycarboxylate　(PCE)　copolymers　were　used　to　prepare　the　calcium-silicate　hydrated　(C-S-H)/PCE　nanocomposites　by　precipitating　C-S-H　from　Na2SiO3·9H2O　and　Ca(NO3)2·4H2O　in　the　PCE　solution.　The　composition　and　structure　of　the　prepared　C-S-H/PCE　nanocomposites　were　characterized　by　XRD,　SEM,　FTIR　methods,　and　the　early　strength　of　mortars　was　measured.　The　results　show　that　structural　investigation　of　the　C-S-H/PCE　nanocomposites　via　X-ray　diffraction　revealed　a　semi-crystalline　composition,　and　the　PCE　polymers　were　adhered　the　surface　of　C-S-H　particles　in　the　composite.　The　preparation　of　C-S-H/PCE　nanocomposites　enhanced　markedly　the　early　strength　of　mortar,　and　when　the　dosage　of　PCE　copolymers　was　up　to　30%,　the　early　strength　enhancing　effect　was　the　highest,　the　early　flexural　strength　increased　up　to　100%,　and　early　compressive　strength　increased　up　to　120%.　Therefore,　C-S-H/PCE　nanocomposites　can　improve　the　early　strength　of　mortar　effectively　since　it　can　lower　the　barrier　of　nucleation　of　the　products,　promote　the　nucleation　and　inhibit　the　growth　of　large　grains　effectively.　©　2017　Trans　Tech　Publications,　Switzerland.