In　this　article,　model-based　diagnosis　(MBD)　is　an　important　fault　diagnosis　method　for　power　distribution　network　faults.　The　minimum　hitting　set　(MHS)　calculation,　as　one　of　the　steps　of　MBD,　has　a　significant　impact　on　the　performance　of　MBD.　However,　the　efficiency　and　accuracy　of　MHS　calculation　limit　the　performance　of　MBD　when　the　distribution　network　has　multiple　multiphase　faults.　To　overcome　these　limitations,　a　hierarchical　MHS　calculation　method　for　multiple　multiphase　faults　is　proposed.　This　method　first　converts　a　single　high-dimensional　MHS　calculation　into　multiple　low-dimensional　MHS　calculations　by　establishing　a　hierarchical　MBD.　In　the　low-dimensional　MHS　calculations,　the　fitness　function　and　MHS　criterion　of　the　MHS　calculation　are　improved　to　enhance　the　versatility　of　the　method　for　different　minimum　conflict　sets,　and　the　exhaustive　method　is　used　instead　of　the　intelligent　algorithm　to　realize　the　search　process.　Finally,　a　14-node　distribution　network　is　taken　as　an　example　to　verify　the　advantages　of　the　hierarchical　MHS　method　in　terms　of　calculation　efficiency　and　accuracy　under　multiple　multiphase　faults.