A　two-phase　flow　unified　pipe　network　method　is　developed　to　simulate　CO2　evolution　in　fractured　saline　aquifers.　Fractures　are　explicitly　represented　in　the　proposed　method.　The　two-phase　flow　in　both　rock　matrix　and　fractures　is　considered　by　using　different　equivalent　pipe　flow　models　respectively,　namely　the　two-phase　matrix　pipe　flow　model　and　the　two-phase　fracture　pipe　flow　model.　The　equivalent　flow　coefficients　of　the　pipe　flow　models　are　derived　based　on　flow　rate　equivalence.　The　coupling　of　the　fracture　pipe.flow　and　matrix　pipe　flow　is　treated　by　applying　the　extended　capillary　pressure　conditions.　Brooks-Corey　relative　permeability　model　and　capillary　model　are　adopted　to　simulate　CO2　(non-wetting　phase)　invasion　into　the　brine　(wetting　phase)　saturated　formation,　which　is　a　typical　drainage　process.　Accurate　Equations　of　State　for　calculating　density　and　viscosity　of　CO2　are　incorporated　to　reflect　its　change　in　hydraulic　characteristics　during　the　injection　processes.　The　proposed　method　is　simple　yet　robust　and　not　sensitive　to　the　mesh　quality.　The　complex　geological　and　topological　features　of　fracture　networks　can,　therefore,　be　well　retained　in　the　proposed　method.　The　anisotropy　and　heterogeneity　characteristics　of　the　fractured　rock　mass　caused　by　the　fracture　networks　can　be　accurately　represented.　The　proposed　method　is　verified　by　comparing　to　other　numerical　methods.　Both　2D　and　3D　models　with　complex　fracture　networks　are　presented　to　demonstrate　the　feasibility　of　proposed　method.　Numerical　examples　show　that　fractures　can　significantly　affect　the　distribution　and　evolution　of　CO2　in　aquifers　and　the　differences　of　entry　capillary　pressures　for　fractures　and　matrix　rock　should　be　accurately　simulated.