The　aerodynamic　performance　of　1.5　high　pressure　cylinder　steam　turbine　stage　with　rotor　blade　tip　labyrinth　and　brush　seals　is　numerically　investigated　using　three-dimensional　ReynoldsAveraged　Navier-Stokes(RANS)　and　SST　turbulence　model　based　on　non-linear　Darcian　porous　model.　The　numerical　prediction　of　the　leakage　flow　rate　of　experimental　brush　seal　is　well　agreement　with　the　experimental　measurements.　The　reliability　of　the　presented　numerical　method　is　validated.　Effect　of　the　rotor　blade　tip　labyrinth　and　brush　seal　on　the　tip　leakage　flow　rate　and　aerodynamic　parameters　of　turbine　stage　is　analyzed　in　detailed.　The　obtained　results　show　that　the　aerodynamic　efficiency　of　turbine　stage　with　rotor　blade　tip　brush　seal　increases　up　to　0.15%　by　comparison　of　the　labyrinth　seal.　In　addition,　the　tip　leakage　flow　rate　of　brush　seal　decreases　by　30.74%　by　comparison　of　labyrinth　seal.　The　similar　influence　of　the　rotor　tip　brush　and　labyrinth　seal　on　the　reaction　degree　and　rotor　blade　exit　flow　angle　is　obtained.　Brush　seal　performs　better　in　sealing　performance　as　the　pressure　drop　across　bristles　is　higher　than　that　across　the　labyrinth　tooth　at　the　same　location　in　labyrinth　shroud　seal.　©　2020,　Science　Press.　All　right　reserved.