In　this　study,　regression　analysis　on　Al2O3/H2O　nanofluid　properties　was　made.　The　growth　and　departure　of　the　bubble　behavior　in　the　Al2O3/H2O　nanofluid　and　pure　water　flow　boiling　process　were　numerically　simulated　based　on　Moving　Particle　Semi-implicit　(MPS)　method　in　different　conditions.　And　the　comparative　analysis　was　made　between　the　results　of　pure　water　and　Al2O3/H2O　nanofluid　under　the　same　conditions.　The　results　indicate　that　the　bubble　in　Al2O3/H2O　nanofluid　grows　faster　and　the　bubble　departure　frequency　of　nanofluids　is　greater　than　that　of　pure　water,　and　the　heat　flux　is　also　improved　in　the　same　conditions.　It　is　convinced　that　nanofluids　can　enhance　the　boiling　heat　transfer.　This　work　also　initially　reveals　the　underlying　mechanism　why　nanofluids　can　enhance　the　boiling　heat　transfer　from　the　point　of　view　of　bubble　dynamic　behavior.　In　order　to　investigate　the　nanofluids　application　in　In-Vessel　Retention　(IVR)　strategy　after　severe　accident　happened　to　the　nuclear　reactor,　the　bubble　dynamic　behavior　has　been　researched.　The　results　indicate　that　the　bubbles　in　nanofluids　can　depart　from　the　heat　surface　earlier　than　that　of　the　pure　water,　and　this　makes　the　new　cooling　fluid　fill　the　heat　surface　timely　and　enhance　the　IVR　capability.