In　the　present　study,　a　3-D　numerical　simulation　of　laminar　film　condensation　of　steam　in　the　presence　of　non　condensable　gas　is　performed　in　horizontal　minichannels　with　six　cross-sectional　shapes　based　on　the　volume　of　fluid　(VOF)　method.　Mixture　of　steam　and　oxygen　enters　the　channel　with　uniform　temperature,　while　the　inlet　volume　fraction　of　oxygen　increases　from　0%　to　3%.　It　is　shown　that　the　existence　of　non-condensable　gas　results　in　significant　reduction　in　the　mass　transfer　rate　from　vapor　to　liquid　along　the　interface　in　the　axial　direction.　And　then　the　heat　transfer　coefficient　of　condensation　with　oxygen　is　demonstrated　to　decline　sharply　compared　with　that　of　the　pure　vapor　condensation.　(C)　2015　Elsevier　Ltd.　All　rights　reserved.