Under　the　background　of　carbon　peaking　and　carbon-neutral,　the　hydrogen-fueled　Wankel　rotary　engine　with　excellent　power　and　emission　characteristic　is　under　the　spotlight.　The　leakage　problem,　especially　the　apex　seal　leakage,　is　considered　to　be　an　important　engineering　problem　restricting　the　development　of　hydrogen-fueled　Wankel　rotary　engine.　To　make　up　for　research　gaps,　this　study　was　conducted　to　investigate　the　effects　of　three　types　of　apex　seal　leakage　on　engine　performance.　Two　methods　for　calculating　the　leakage　area　of　spark　plug　cavities　are　proposed　and　compared,　and　the　definition　method　based　on　leakage　direction　is　more　consistent　with　the　experimental　results.　The　leading　spark　plug　leakage　and　corner　seal　leakage　has　the　greatest　impact　on　peak　pressure　and　IMEP,　which　reduce　the　peak　value　of　pressure　by　0.249　MPa　and　0.047　MPa,　and　reduce　the　IMEP　by　8.68　%　and　10.51　%　respectively.　In　addition　to　reducing　the　leakage　area,　reducing　the　distance　between　leading　spark　plug　and　minor　axis　by　5.5　mm　could　increase　the　peak　pressure　by　0.2　MPa　and　reduce　the　leakage　from　the　working　chamber　to　the　adjacent　chambers　from　0.055　g　to　0.038　g.