Plastic　metals　and　low-dimensional　materials　are　extensively　utilized　as　reinforcements　in　fabricating　bio-inspired　staggered　composites.　Here,　we　introduce　a　comprehensive　analytical　model　to　investigate　the　influence　of　reinforcement　plasticity　on　the　mechanical　properties　of　staggered　composites　while　preserving　the　non-linear　plastic　characteristics　of　the　matrix.　Competitive　plastic　deformation　in　both　the　reinforcement　and　the　matrix　leads　to　two　distinct　deformation　modes:　reinforcement-first　yield　or　matrix-first　yield.　Each　mode　exhibits　different　stages　of　deformation　and　failure　in　plastic　staggered　composites.　Our　analytical　formulae,　validated　via　finite　element　analysis,　establish　connections　between　effective　stress　and　strain　responses,　material　compositions,　and　structural　geometry,　thereby　revealing　non-linear　shear　stress　transfer　and　plastic　evolution　mechanisms.　Furthermore,　we　discover　that　tailoring　the　plasticity　of　the　reinforcement　while　maintaining　the　dominant　plastic　deformation　of　the　matrix,　can　overcome　the　trade-off　between　composite　strength　and　ductility.　Our　model　provides　valuable　insights　into　designing　high-performance　metal-reinforced　staggered　composites　and　can　be　further　extended　to　explore　the　mechanical　properties　of　plastic　low-dimensional　material-reinforced　nanocomposites　with　noncovalent　interfaces.　©　2025