Single-atom　catalysts　(SACs)　have　attracted　extensive　attention　in　the　field　of　heterogeneous　catalysis.　However,　the　fabrication　of　SACs　with　high　loading　and　high-temperature　stability　remains　a　grand　challenge,　especially　on　oxide　supports.　In　this　work,　we　have　demonstrated　that　through　strong　covalent　metal-support　interaction,　high-loading　and　thermally　stable　single-atom　Pt　catalysts　can　be　readily　prepared　by　using　Fe　modified　spinel　as　support.　Better　catalytic　performance　in　N2O　decomposition　reaction　is　obtained　on　such　SACs　than　their　nanocatalyst　counterpart　and　low-surface-area　Fe2O3　supported　Pt　SACs.　This　work　provides　a　strategy　for　the　fabrication　of　high-loading　and　thermally　stable　SACs　for　applications　at　high　temperatures.