This　article　investigates　a　comprehensive　analysis　of　the　bending　problem　pertaining　to　magneto-electro-elastic　(MEE)　nanobeams　on　the　Winkler-Pasternak　foundation.　Taken　into　account　the　influence　of　size　effects　of　nano　structures,　a　non-classical　mechanical　model　is　established　to　describe　the　bending　behavior　for　MEE　nanobeams.　In　this　research,　the　nonlocal　modified　couple　stress　theory　is　utilized　to　accurately　capture　both　the　softening　and　hardening　effects　resulting　from　the　size　effect.　The　theory　of　third-order　shear　deformation　and　von　Karman　geometric　nonlinear　theory　are　employed　in　conjunction　with　the　introduction　of　Maxwell＇s　equation　to　develop　the　model　of　MEE　nanobeam,　the　control　equation　of　the　nonlinear　bending　problem　of　MEE　nanobeams　is　obtained　by　Minimum　potential　energy　principle,　and　it　is　solved　by　Galerkin　method.　Finally,　this　study　provides　a　detailed　discussion　on　the　influences　of　the　ratio　of　nonlocal　parameters　and　length-scale　parameters,　Winkler-Pasternak　coefficient,　external　magnetic　potential,　external　voltage　and　span-thickness　ratio　on　nonlinear　deflection　of　nanobeam.　©　2023　Elsevier　Masson　SAS