Magnesium　alloys,　as　a　new　type　of　biodegradable　medical　metal　material,　have　a　promising　application　in　the　field　of　vascular　stents.　However,　the　poor　deformability　of　Mg　alloys　due　to　hexagonal　close-packed　(hcp)　structure　makes　it　difficult　to　fabricate　their　thin　tube.　In　this　study,　the　micro-tubes　of　Mg-4Zn-0.2Mn-0.2Ca　alloy,　a　new　type　of　degradable　magnesium　alloy,　with　3.1~3.6　mm　in　outer　diameter　and　0.25~0.4　mm　in　wall　thickness　were　prepared　by　hot　extrusion-drawing　composite　process.　The　microstructure　evolution　and　mechanical　properties　of　the　one　with　3.6　mm　in　outer　diameter,　0.4　mm　in　wall　thickness　show　that　the　crystal　slip,　twins　and　recrystallization　occur　during　the　plastic　deformation　of　the　tubes,　and　the　work　hardening　is　significant.　This　drawn　tube　exhibits　a　tensile　strength　of　427.3　MPa,　yield　strength　of　383.4　MPa,　and　elongation　of　5.2%.　After　annealing　at　300℃　for　30　min,　the　microstructure　becomes　uniform　and　the　elongation　increases　to　18.0%,　which　is　conducive　to　the　fabrication　of　vascular　stents.　©　2020,　Science　Press.　All　right　reserved.