A　comprehensive　three-dimensional　transient　model　is　developed　for　the　evolution　of　the　temperature　field　during　the　vertical　wall　manufacturing　process　using　coaxial　laser　metal　deposition　(LMD),　the　material　manufactured　is　directional　solidification　(DS)　superalloy　Rene80.　The　interaction　between　laser　and　powder　during　the　powder　falling　process　is　simulated,　and　its　possible　effect　on　the　temperature　field　of　molten　pool　is　analyzed.　After　that,　the　evolution　of　temperature　field　during　the　vertical　wall　manufacturing　process　is　studied.　By　numerical　simulation,　the　change　of　phase　(solid/liquid,　and　mushy　zone)　and　the　liquid　flowing　are　considered　and　the　parameters　are　from　optimized　vertical　wall　manufacturing　experiments.　The　results　reproduce　the　shape　changing　of　the　molten　pool　and　the　instability　of　laser　metal　deposition　process.　The　changing　rule　of　temperature　field　is　in　conformity　with　that　of　real　vertical　wall　manufacturing　experiment.　©,　2015,　Science　Press.　All　right　reserved.