Experiments　were　conducted　to　investigate　the　heat　transfer　characteristics　of　supercritical　pressure　water　in　an　annular　flow　channel　with　a　gap　size　of　4　mm　at　the　pressure　of　23-28　MPa,　mass　velocity　of　350-1000　kg/(m2·s)　and　heat　flux　of　200-1000　kW/m2.　The　results　show　that,　at　the　conceptual　design　parameters　of　SCWR,　no　heat　transfer　deterioration　occurred,　and　the　heat　flux　and　mass　flux　had　significant　influence　on　heat　transfer.　The　wrapped　wire　arranged　on　the　heated　rod　had　a　remarkable　effect　on　local　heat　transfer,　and　it　could　also　improve　the　heat　transfer　in　downstream.　At　particular　test　parameters,　heat　transfer　deterioration　was　observed　in　the　annular　channel,　and　the　mass　flux　and　heat　flux　corresponding　to　deterioration　were　close　to　those　predicted　by　the　Ogata　correlation.　According　to　the　criterion　of　Jackson,　the　heat　transfer　deterioration　may　be　mainly　caused　by　buoyancy.　The　comparison　between　the　six　heat-transfer　correlations　selected　and　the　experimental　data　shows　that　the　Jackson＇s　correlation　and　the　Bishop＇s　correlation　perform　best　and　they　can　be　used　in　predicting　heat　transfer　of　supercritical　water　in　annular　flow　channels.