This　paper　presents　an　investigation　of　wave　propagation　through　microfractured　rock　mass.　The　effects　of　microfracture　on　wave　propagation　were　observed　by　a　series　of　scanning　electron　microscope　(SEM)　tests　and　wave-velocity　measurements.　A　spectrum　analysis　was　introduced　to　analyze　the　attenuation　coefficient　and　the　wave　number　of　seismic　waves　propagating　through　microfractured　rock　mass.　The　effects　of　fracture　length,　fracture　quantity,　and　frequency　of　incident　wave　on　the　attenuation　rate,　effective　velocity,　attenuation　coefficient,　and　wave　number　were　numerically　simulated　and　discussed.　The　results　demonstrate　that　the　attenuation　rate,　effective　velocity,　attenuation　coefficient,　and　wave　number　are　significantly　influenced　by　the　geometrical　parameters　of　microfracture　(e.g.,　length　and　quantity).　In　addition,　the　numerical　manifold　method　(NMM)　was　validated　as　a　method　for　investigating　the　dynamic　behavior　of　heavy　microfractured　rock　mass　efficiently.　(C)　2017　American　Society　of　Civil　Engineers.