A　series　of　tensile　tests　of　as-solid-solution　treated　AZ91D　wrought　magnesium　alloys　were　carried　out　at　strain　rates　ranging　in　1.11　×　10-4-1.67　×　10-3　s-1　and　temperatures　ranging　in　248-523　K.　The　results　show　that　there　occurs　a　dynamic　strain　aging　(DSA)　phenomenon　during　deformation　of　AZ91D　magnesium　alloy　in　certain　ranges　of　temperature　and　strain　rate.　The　typical　characteristics　of　DSA　include　serrated　flow,　the　corresponding　related　serrated　types　are　defined　as　type　A　and　type　A+B.　Negative　strain-rate　sensitivity　and　peak　of　work-hardening　rate　appear.　The　critical　plastic　strain　for　the　onset　of　serrations　decreases　with　increasing　deformation　temperature,　while　it　increases　with　increasing　strain　rate.　Moreover,　the　work-hardening　rate　increases　sharply　with　increasing　temperature　when　the　deformation　temperature　is　higher　than　323　K,　and　reaches　the　peak　value　at　368　K.