Based　on　the　data　of　rammed　soil-cement　pile　composite　foundation　loading　tests,　the　settlement　rate　of　composite　foundation　is　used　as　an　analytical　variable　considering　its　randomness　and　fuzziness　of　the　failure.　The　membership　function　of　the　failure　state　is　obtained　by　fuzzy　statistic　method　and　the　parameter　distributing　of　the　variable　is　obtained　with　the　probability　statistic　method.　From　the　concept　of　probability　theory　and　fuzzy　mathematics,　the　calculation　method　of　fuzzy　random　reliability　of　composite　foundation　losing　its　stability　have　been　established　and　the　reliability　index　of　rammed　soil-cement　pile　composite　foundation　based　on　load　test　have　been　analyzed　through　examples.