In　the　forthcoming　fifth　generation　(5G)　cellular　networks,　caching　and　virtualization　have　been　considered　as　promising　techniques.　In　this　paper,　we　consider　a　hierarchical　caching　architecture　that　core　network　and　radio　access　network　(RAN)　have　caching　capability　with　virtualization.　Thus　how　to　share　caching　resources　among　mobile　virtual　network　operators　(MVNOs)　is　an　important　issue,　which　is　formulated　as　a　competitive　game　to　maximize　their　expected　revenues　based　on　the　oligopoly　market　model.　We　decompose　the　optimization　problem　into　two　independent　caching　resource　sharing　problems　in　RAN　and　core　network,　respectively.　Local　optimal　solutions　are　solved　and　the　global　Nash　equilibrium　solution　is　achieved.　Finally,　simulation　results　are　illustrated　to　demonstrate　the　performance　of　the　proposed　scheme.　©　2018　IEEE.