The　conventional　mono-chemotherapy　still　suffers　from　unsatisfied　potency　for　cancer　therapy　due　to　tumor　heterogeneity　and　the　occurrence　of　drug　resistance.　Combination　chemotherapy　based　on　the　nanosized　drug　delivery　systems　(nDDSs)　has　been　developed　as　a　promising　platform　to　circumvent　the　limitations　of　mono-chemotherapy.　In　this　work,　starting　from　cisplatin　and　curcumin　(Cur),　we　prepared　a　dual　drug　backboned　shattering　polymeric　nDDS　for　synergistic　chemotherapy.　By　in　situ　polymerization　of　the　Cur,　platinum　(IV)　complex-based　prodrug　monomer　(DHP),　L-lysine　diisocyanate　(LDI),　and　then　conjugation　with　a　hydrophilic　poly　(ethylene　glycol)　monomethyl　ether　(mPEG)　derivative,　a　backbone-type　platinum　(IV)　and　Cur　linkage　containing　mPEG-poly(platinum-co-Cur)-mPEG　(PCPt)　copolymer　was　synthesized.　Notably,　the　platinum　(IV)　(Pt　(IV))　and　Cur　were　incorporated　into　the　hydrophobic　segment　of　PCPt　with　the　fixed　drugs　loading　ratio　and　high　drugs　loading　content.　The　batch-to-batch　variability　could　be　decreased.　The　resulting　prodrug　copolymer　then　self-assembled　into　nanoparticles　(PCPt　NPs)　with　an　average　diameter　around　100　nm,　to　formulate　a　synergetic　nDDS.　Importantly,　PCPt　NPs　could　greatly　improve　the　solubility　and　stability　of　Cur.　In　vitro　drug　release　profiles　have　demonstrated　that　PCPt　NPs　were　stable　in　PBS　7.4,　rapid　burst　release　was　greatly　decreased,　and　the　Pt　and　Cur　release　could　be　largely　enhanced　under　reductive　conditions　due　to　the　complete　dissociation　of　the　hydrophobic　main　chain　of　PCPt.　In　vitro　cell　viability　test　indicated　that　PCPt　NPs　were　efficient　synergistic　chemotherapy　units.　Moreover,　PCPt　NPs　were　synergistic　for　cisplatin-resistant　cell　lines　A549/DDP　cells,　and　they　exhibited　excellent　reversal　ability　of　tumor　resistance　to　cisplatin.　This　work　provides　a　promising　strategy　for　the　design　and　synthesis　of　nDDS　for　combination　chemotherapy.　©　2020　by　the　authors.