A　new　mathematic　model　of　the　fatigue　damage　of　tires　was　proposed　using　system　analysis　method　and　signal　process.　The　parameters　of　fatigue　damage　in　the　composite　structures　were　obtained　in　this　paper.　Relationships　between　the　fatigue　damage　parameter　and　detection　of　fatigue　damage　in　the　tire　structure　were　discussed　and　illustrated.　The　results　show　that　the　established　crack　growth　MODEL　proposed　in　the　paper　can　more　really　reveal　the　process　of　the　fatigue　damage　in　the　rubber　and　fiber-rubber　composite　structure　numerically.　The　results　of　the　test　indicate　that　the　system　analysis　method　is　MORE　effective　in　the　on-line　detection　of　the　growth　process　of　the　delamination　crack　between　layers　in　the　complex　composite　structures.