With　the　gradual　depletion　of　the　world＇s　oil　and　gas　resources,　heavy　oil　recovery　has　become　increasingly　important.　Supercritical　water　flooding　is　a　promising　enhanced　oil　recovery　technology　because　it　could　enhance　deep　extra　heavy　oil　recovery　and　in-situ　upgrade　the　recovered　oil.　It　is　critical　to　predict　the　injection　parameters　to　make　the　pilot　program　of　supercritical　water　injection.　In　this　paper,　a　computational　model　has　been　developed　for　predicting　supercritical　water　injection　in　wellbores.　Frictional　pressure　drop　correlations　are　selected　according　to　different　flow　patterns.　For　single-phase　flow　of　supercritical　water,　resistance　coefficients　in　critical　area　are　modified.　The　calculation　results　agree　well　with　the　field　test　results.　And　the　influences　of　injection　parameters　on　flow　and　heat　transfer　are　analyzed.　©　2018,　Science　Press.　All　right　reserved.