To　prepare　hydrated　magnesium　silicate　cement　with　excellent　flowability　and　early　compressive　strength,　orthogonal　experiments　were　conducted　to　study　the　effects　of　magnesium　silicon　ratio　(Mg/Si),　water　cement　ratio　(W/B),　and　sodium　hexametaphosphate　(SHMP)　on　flowability　and　compressive　strength　at　3　and　28　days,　in　order　to　determine　the　optimal　mix　ratio.　The　results　indicate　that　Mg/Si　has　a　small　impact　on　early　compressive　strength　and　flowability,　but　a　significant　impact　on　later　compressive　strength.　W/B　and　SHMP　have　a　significant　impact　on　early　compressive　strength　and　flowability.　The　optimal　mix　ratio　of　hydrated　magnesium　silicate　cement　was　determined　through　range　and　variance　analysis:　Mg/Si　of　1.2　(molar　ratio),　W/B　of　0.41,　and　SHMP　of　3.4%.　The　influence　of　various　factors　on　the　phase　composition　and　microscopic　morphology　of　hydrated　magnesium　silicate　cement　was　analyzed　by　XRD,　SEM　and　other　microscopic　tests.　It　was　found　that　the　content　of　Mg(OH)2　in　the　optimized　sample　was　significantly　reduced,　and　the　M-S-H　gel　was　more　uniform　and　dense.　©　2023　Journal　of　Functional　Materials.　All　rights　reserved.