To　systematic　study　the　factors　which　influence　the　braking　torque　in　liquid-cooled　eddy　current　retarder　with　a　structure　of　two　salient　poles,　we　analyze　the　related　theory　of　electromagnetics　and　the　formulas　for　the　braking　torque　of　eddy　current　retarder　(ECR)　were　deduced　on　the　basis　of　the　working　principle　of　liquid-cooled　ECR　with　a　structure　of　two　salient　poles.　And　the　braking　system　model　was　built,　the　electrical　conductivity　and　magnetic　permeability　of　materials,　the　excitation　current　and　the　rotor　speed　on　retarder　braking　torque　have　been　studied　by　JMAG　software.　The　theoretical　and　finite　element　analysis　was　verified　and　the　general　regularity　of　the　influence　factors　of　braking　torque　in　liquid-cooled　ECR　was　obtained　through　the　prototype　test.　©　2014,　Journal　of　Chemical　and　Pharmaceutical　Research.　All　rights　reserved.