The　real-time　dynamic　simulation　model　of　a　600MW　lignite-fired　pulverized　boiler,　which　is　a　supercritical　once-through　boiler　with　fan　mill　three　drying　media　direct　fired　system,　was　established.　The　step　reduction　of　hot　flue　gas　flow　rate　was　simulated.　The　dynamic　responses　of　live　and　reheat　steam　temperatures　were　obtained　and　analyzed.　Results　show　that　the　response　of　steam　temperature　is　an　oscillation　process.　The　superheat　and　reheat　steam　overtemperature　values　are　influenced　by　the　boiler　load,　the　hot　flue　gas　extracting　percent　and　the　inertia　time　of　pulverizing　system.　(C)　2014　The　Authors.　Published　by　Elsevier　Ltd.