The　moving　least　squares　(MLS)　interpolation　gets　rid　of　the　shackles　of　meshes,　while　the　numerical　manifold　method　(NMM)　can　solve　both　continuity　and　discontinuity　problems　in　a　unified　way.　The　MLS-based　NMM　(abbreviated　as　MLS-NMM)　inherits　the　individual　merits　of　MLS　and　NMM.　In　the　present　work,　the　MLS-NMM　is　extended　to　solve　groundwater　flow　problems　in　heterogeneous　porous　media.　To　accurately　simulate　the　flow　velocity　field　at　and　in　the　vicinity　of　the　material　interfaces,　the　refraction　law　is　introduced　into　the　proposed　model　as　a　posteriori　condition.　Several　examples　are　employed　to　verify　the　correctness　and　accuracy　of　the　proposed　model.　The　results　indicate　that　the　MLS-NMM　can　model　the　Darcy　flow　in　heterogeneous　porous　media　with　high　accuracy,　as　well　as　satisfy　the　refraction　law　rigorously.　In　addition,　the　smooth　flow　velocity　field　can　be　obtained　directly　without　the　need　for　extra　post-processing.