For　the　nondeterministic　factors　of　an　aeroengine　blisk,　including　both　factors　with　sufficient　and　insufficient　statistical　data,　based　on　the　dynamic　substructural　method　of　determinate　analysis,　the　extremum　response　surface　method　of　probabilistic　analysis,　and　the　interval　method　of　nonprobabilistic　analysis,　a　methodology　called　the　probabilistic　and　nonprobabilistic　hybrid　reliability　analysis　based　on　dynamic　substructural　extremum　response　surface　decoupling　method　(P-NP-HRA-DS-ERSDM)　is　proposed.　The　model　includes　random　variables　and　interval　variables　to　determine　the　interval　failure　probability　and　the　interval　reliability　index.　The　extremum　response　surface　function　and　its　flow　chart　of　mixed　reliability　analysis　are　given.　The　interval　analysis　is　embedded　in　the　most　likely　failure　point　in　the　iterative　process.　The　probabilistic　analysis　and　nonprobabilistic　analysis　are　investigated　alternately.　Tuned　and　mistuned　blisks　are　studied　in　a　complicated　environment,　and　the　results　are　compared　with　the　Monte　Carlo　method　(MCM)　and　the　multilevel　nested　algorithm　(MLNA)　to　verify　that　the　hybrid　model　can　better　handle　reliability　problems　concurrently　containing　random　variables　and　interval　variables;　meanwhile,　it　manifests　that　the　computational　efficiency　of　this　method　is　superior　and　more　reasonable　for　analysing　and　designing　a　mistuned　blisk.　Therefore,　this　methodology　has　very　important　practical　significance.