Equivalent　continuum　models　estimating　the　deformability　of　complexly　fractured　rock　masses　may　incur　significant　discrepancies.　This　paper　proposes　an　equivalent　discrete　fracture　network　(E-DFN)　method　to　proficiently　capture　the　non-continuous　characteristics　of　rock　masses　while　significantly　reducing　computational　cost　compared　with　traditional　discrete　fracture　network　(DFN)　models.　A　significance　index　of　individual　fractures　is　defined　to　quantitatively　evaluate　their　impact　on　the　elastic　modulus.　Accumulative　significance　indices　are　then　generated　to　define　E-DFNs　containing　representative　quantities　of　fractures.　Numerical　simulations　are　conducted　with　E-DFN　models　using　UDEC　(universal　distinct　element　code).　The　relationship　between　elastic　moduli　of　complexly　fractured　rocks　and　models　with　E-DFNs　is　established　by　an　extrapolation　function　obtained　through　regression　analyses　based　on　an　assumption　of　the　marginal　diminishing　effect　of　modulus　reduction.　The　proposed　method　is　validated　by　stochastic　DFNs　with　different　geometric　configurations.　The　results　show　that　reasonable　estimation　with　small　errors　is　achieved　by　the　extrapolation　of　density-reduced　E-DFN　models.　The　E-DFN　method　strikes　a　balance　between　result　reliability　and　computational　intensity.　©　2020　Elsevier　B.V.