A　6　kW　fiber　laser　YSL-6000　was　chosen　to　weld　the　E36　steel　with　a　thickness　of　6　mm.　The　effects　of　laser　welding　speeds　on　the　welded　joint　appearance　were　examined,　and　the　microstructures　and　properties　on　the　typical　butt　joints　were　investigated.　Results　showed　that　narrow　and　fully　penetrated　welded　joints　without　obvious　defects　could　be　obtained　at　different　welding　speeds.　With　the　welding　speed　increasing,　the　welding　seam　width　decreased,　and　the　welding　seam　(WS)　and　heat　affected　zone　(HAZ)　hardness　increased.　The　microstructures　of　weld　metal　and　HAZ　were　consisted　of　martensite,　but　the　contents　of　it　were　significantly　different.　Welding　speeds　had　no　remarkable　effect　on　the　tensile　strength　and　yield　strength,　except　elongation.　But　the　increase　of　welding　speeds　resulted　in　improvement　of　micro-hardness,　which　reached　the　maximum　value　of　426.38　HV　at　45　mm/s.　Weld　metals　of　different　welded　joints　were　active　in　corrosion　solution,　and　corrosion　potential　became　more　negative　with　the　welding　speeds　increased　from　35　mm/s　to　50　mm/s,　except　at　45　mm/s.