The　dynamic　mechanical　property　and　microstructure　evolution　of　commercial　pure　titanium　with　initial　lamellar　dislocation　boundary　structures　were　studied　at　different　strain　rate　compression.　The　experiments　were　conducted　to　the　cylindrical　specimens　using　Gleeble-3500　thermal-mechanical　simulation　machine　at　room　temperature.　With　increasing　of　the　strain　rate,　strain　rate　strengthening　effect　was　found　in　the　material.　New　dislocation　boundary　structures　along　impact　direction　were　generated　which　perpendicular　to　initial　dislocation　boundary.　Then　the　S　bands　boundary　structure　was　formed　by　interaction　between　new　and　initial　dislocations.　It　can　be　supposed　that　initial　dislocation　boundary　are　sheared　and　kinked　by　new　dislocation　slipping.