Engineered　cementitious　composites　(ECC)　used　as　runway　pavement　material　may　suffer　different　strain　rate　loads　such　as　aircraft　taxiing,　earthquakes,　crash　impacts,　or　blasts.　In　this　paper,　the　dynamic　tensile　behaviors　of　the　steel　grid-polyvinyl　alcohol　(PVA)　fiber　and　KEVLAR　fiber-reinforced　ECC　were　investigated　by　dynamic　tensile　tests　at　medium　strain　rates.　The　mixture　was　designed　with　different　volume　fractions　of　fibers　and　layer　numbers　of　steel　grids　to　explore　the　reinforcement　effectiveness　on　the　dynamic　performance　of　the　ECC.　The　volume　fractions　of　these　two　types　of　fibers　were　0%,　0.5%,　1%,　1.5%,　and　2%　of　the　ECC　matrix,　respectively.　The　layer　numbers　of　the　steel　grid　were　0,　1,　and　2.　The　dynamic　tensile　behaviors　of　the　PVA　fiber　and　the　KEVLAR　fiber-reinforced　ECC　were　also　compared.　The　experimental　results　indicate　that　under　dynamic　tensile　loads,　the　PVA-ECC　reveals　a　ductile　and　multi-cracking　failure　behavior,　and　the　KEVLAR-ECC　displays　a　brittle　failure　behavior.　The　addition　of　the　PVA　fiber　and　the　KEVLAR　fiber　can　improve　the　tensile　peak　stress　of　the　ECC　matrix.　For　the　specimens　A0.5,　A1,　A1.5,　and　A2.0,　the　peak　stress　increases　by　84.3%,　149.4%,　209.6%,　and　237.3%,　respectively,　compared　to　the　matrix　specimen.　For　the　specimens　K0.5,　K1,　K1.5,　and　K2,　the　peak　stress　increases　by　about　72.3%,　147.0%,　195.2%,　and　263.9%,　respectively,　compared　to　the　matrix　specimen.　The　optimum　fiber　volume　content　is　1.5%　for　the　PVA-ECC　and　the　KEVLAR-ECC.　The　KEVLAR-ECC　can　supply　a　higher　tensile　strength　than　the　PVA-ECC,　but　the　PVA-ECC　reveals　more　prominent　deformation　capacity　and　energy　dissipation　performance　than　the　KEVLAR-ECC.　Embedding　steel　grid　can　improve　the　tensile　peak　stress　and　the　energy　dissipation　of　the　ECC　matrix.　For　the　strain　rate　of　10(-3)　s(-1),　the　peak　stress　of　the　A0.5S1　and　A0.5S2　specimens　increases　by　about　49.1%　and　105.7%　compared　to　the　A0.5　specimen,　and　the　peak　stress　of　the　K0.5S1　and　K0.5S2　specimens　increases　by　about　61.5%　and　95.8%,　respectively,　compared　to　the　K0.5　specimen.