Addressing　the　contradiction　between　the　magneto-rheological　properties　and　dispersion　stability　of　MRFs　poses　a　significant　challenge　in　the　preparation　process.　This　paper　proposes　a　micro-nano　composite　material　design　scheme　using　graphene　oxide　as　a　grafting　agent　to　encapsulate　nanoscale　magnetite　(Fe3O4)　particles　onto　the　surface　of　carbonyl　iron　powders.　The　prepared　micro-nano　composite　magnetic　microspheres　achieve　a　reduction　in　density　for　enhanced　stability　while　ensuring　no　compromise　in　magnetic　performance.　The　effectiveness　of　the　preparation　process　is　ensured　through　the　analysis　of　the　microscopic　morphology,　crystal　structure,　and　elemental　characteristics　of　all　process　products　using　Field　Emission　Scanning　Electron　Microscopy　(FE-SEM),　powder　X-ray　diffraction　(XRD),　Raman　Spectroscopy,　and　Fourier　Transform　Infrared　Spectroscopy　(FTIR).　To　obtain　MRFs　more　suitable　for　magneto-rheological　damper　applications,　this　study　synthesized　micro-nano　composite　MRFs　with　different　base　liquids　and　varying　volume　fractions.　The　stability　and　magneto-rheological　properties　of　each　sample　were　analyzed　through　visual　techniques　and　rheological　testing　platforms.　The　results　indicated　that　micro-nano　composite　MRFs　based　on　40%　to　50%　silicone　oil　exhibit　superior　stability　in　various　aspects,　including　sedimentation　stability,　redispersion　stability,　and　temperature　stability.　Additionally,　the　micro-nano　composite　MRFs　demonstrated　significantly　enhanced　magnetic　performance　compared　to　pure　micrometer-sized,　pure　nanometer-sized,　and　micro-nano　hybrid　MRFs.　©　2024　Elsevier　B.V.