Clarifying　the　soil　microbial　metabolism　and　resource　limitations　could　help　to　understand　the　functions　and　processes　of　aboveground　ecosystems,　as　well　as　to　predict　ecosystem　stability　under　global　climate　change.　Karst　tiankeng　is　a　kind　of　large-scale　negative　surface　terrain　on　the　surface　which　is　similar　to　an　oasis　in　degraded　karst　landscapes,　but　their　soil　microbial　resource　limitations　still　unclear.　In　this　study,　we　evaluated　and　compared　the　soil　microbial　resource　limitation　in　non-degraded　tiankeng　(NDT),　moderately　degraded　tiankeng　(MDT),　heavily　degraded　tiankeng　(HDT),　and　outside　tiankeng　(OT)　by　calculating　soil　ecoenzymatic　stoichiometry.　Overall,　soil　microbial　communities　were　more　limited　by　C　and　P　in　karst　tiankeng　ecosystem.　The　soil　microbial　C　and　P　limitations　significantly　differed　with　the　karst　tiankeng　degradation　increased,　and　the　lowest　C　and　P　limitations　were　observed　in　NDT.　The　higher　microbial　C　and　P　limitations　were　observed　in　OT.　Linear　regression　and　redundancy　analysis　indicated　that　soil　microbial　C　and　P　limitations　were　significantly　influenced　by　soil　nutrients.　Karst　tiankeng　degradation　influence　the　biogeochemical　cycle　and　function　of　karst　tiankeng　systems.　Our　results　highlight　that　karst　tiankeng　(especially　the　NDT)　can　provide　a　stable　habitat　for　the　survival　of　microorganisms　in　karst　areas.　Karst　tiankeng　is　essential　for　regional　ecological　restoration　and　biodiversity　conservation.　Copyright　©　2022　Jiang,　Li　and　Zeng.