To　improve　the　utilization　of　crop　straws　as　a　resource　and　the　compatibility　between　straw　fibers　and　cement-based　materials,　the　hydration　of　modified　straw　fiber　cement-based　composite　(SFCC)　was　studied.　The　structural　characteristic　of　SFCC　was　investigated　by　FTIR,　SEM,　and　XRD.　The　results　show　that　the　setting　time　of　several　modified　straw　fiber　SFCC　pastes　was　shorter　than　that　of　the　unmodified　straw　fiber　SFCC　paste,　and　the　best　method　of　fiber　modification　to　improve　the　setting　time　of　the　SFCC　paste　is　Na2O　center　dot　nSiO(2)　treatment.　The　recommended　fiber　modification　method　for　improving　the　compatibility　between　straw　fibers　and　cement-based　materials　is　alkali　modification,　followed　by　pure　acrylic　emulsion　modification　and　Na2O　center　dot　nSiO(2)　modification.　To　improve　the　strength　of　SFCC,　the　straw　fiber　should　be　modified　by　alkali,　followed　by　pure　acrylic　emulsion　and　Na2O　center　dot　nSiO(2)　modification　and　the　method　of　water　modification　is　also　recommended.　The　phase　types　and　relative　contents　of　crystalline　hydration　products　mixed　with　the　modified　straw　fiber　SFCC　are　significantly　higher　than　those　of　the　unmodified　fiber　SFCC.　The　fiber　treatment　method　that　was　most　helpful　to　increase　the　structural　density　of　hydrates　of　SFCC　was　alkali　treatment　and　pure　acrylic　emulsion　treatment,　followed　by　Na2O　center　dot　nSiO(2)　treatment.