The　deformation　twins　of　commercial　pure　titanium　were　investigated　under　the　split　Hopkinson　pressure　bar　compression　with　different　strain　rates.　It　was　demonstrated　that　the　types　of　twins　induced　by　high-speed　compression　included　{11　(2)　over　bar2},　{11　(2)　over　bar4}　contraction　twins　and　{10　(1)　over　bar2},　{11　(2)　over　bar1}　extension　twins.　Furthermore,　the　quantities　of　the　deformation　twins　at　the　high　strain　rates　were　more　pronounced　than　those　at　the　low　to　medium　speed　deformation.　The　content　of　{11　(2)　over　bar2}　twin　increased　with　the　strain　rate,　while　{11　(2)　over　bar1}　twin＇s　quantity　decreased　slightly　with　the　increasing　strain　rate.　The　semi-quantitative　relationship　between　twin　density　and　strain　rates　was　derived　and　discussed,　which　indicated　that　twin　density　was　nonlinearly　proportional　to　the　strain　rate.　(C)　2015　Elsevier　Inc.　All　rights　reserved.