The　harmonic　error　characteristics　of　the　electromagnetic　current　transformer　are　researched　in　experiments　and　analysis　with　four　kinds　of　electromagnetic　materials　including　nanocrystalline,　permalloy,　silicon　steel　sheet　and　mn-zn　ferrite.　Based　on　the　hysteresis　characteristics　of　these　materials,　the　error　characteristics　including　the　phase　error　and　the　ratio　error　under　various　harmonic　conditions　are　studied　experimentally.　The　results　show　that　the　errors　are　seriously　affected　by　the　harmonic　frequency　and　amplitude.　The　research　can　provide　a　good　reference　for　the　selections　and　applications　of　electromagnetic　current　transformers.　©　2019　IEEE.