In　the　previous　exoskeleton　research,　the　development　method　of　the　exoskeleton-function-expectation　prediction　in　the　initial　design　stage　is　lacking,　which　is　not　conducive　to　reviewing　the　system-parameter　influences　on　exoskeleton　performances,　nor　to　exploring　the　exoskeleton　optimization　direction.　In　this　paper,　a　human-exoskeleton　oscillation　model　is　designed　by　integrating　the　main　functions　of　one　load-supporting　exoskeleton　in　the　gravity　direction　into　the　double-mass　coupled　oscillator　model.　The　model　simplifies　the　human-exoskeleton　coupling　motion　into　the　human-exoskeleton　oscillation　motion　in　the　gravity　direction,　and　in　the　oscillation　process　qualitatively　calculates　the　multiple　functional　expectations　of　the　exoskeleton,　such　as　the　load-supporting　capability,　the　human-exoskeleton　interaction　force,　the　oscillation　response　of　the　backpack　and　the　power-assistance　ability.　By　comparing　the　test　results　of　the　model　with　previous　research,　the　model　performance　was　analyzed.　And　further,　the　reasons　for　the　unsatisfying　load-supporting　efficiency　of　previous　exoskeletons　were　explained　and　the　influences　of　system　parameters　for　the　system　expectations　were　evaluated,　which　helps　to　provide　a　theoretical　basis　for　improving　the　exoskeleton　load-supporting　efficiency　and　human-body　comfort.　In　addition,　the　combination　of　the　exoskeleton　supporting　static　load　and　the　suspension　system　buffering　dynamic　load　is　a　new　direction,　and　the　model　of　the　paper　is　also　beneficial　to　evaluate　the　interference　degree　of　the　exoskeleton　to　the　suspension　system.　©　2023　Elsevier　Inc.