The　coaxial　annular　channels＇　experimental　platform　is　built　to　study　its　flow　characteristics　when　S/d0=2.0,　S/d0=2.5,　S/d0=3.0,　and　it　is　compared　with　circular　pipe＇s　theoretical　value.　The　purpose　is　to　study　the　influence　of　flow　rate,　pressure,　flux,　heat　transfer　temperature　and　geometric　parameters　on　the　coaxial　annular　channels＇　flow　characteristics　of　spiral　tube　heat　exchanger.　The　results　show　that　for　the　same　annulus　width　and　outside　diameter　of　spiral　tube,　annular　channels＇　import,　export　and　total　resistance　coefficients　are　decreasing　and　tend　to　constants　gradually　as　Reynolds　number　increases;　all　the　resistance　coefficients　of　annular　channel＇s　outer　ring　are　bigger　than　those　of　annular　channel＇s　middle　ring　and　inner　ring.　But　the　resistance　coefficients　of　annular　channel＇s　middle　ring　and　inner　ring　are　equal;　under　the　same　Reynolds　number,　the　smaller　the　annulus　width　is,　the　bigger　pressure　drop　of　annular　channel　is.