A CDDP complex is formed by complexation of CDDP and a polymer having a structure of Formula (I). The CDDP complex has good biocompatibility and is degradable. A side chain of the polymer is grafted with polyethylene glycol, which gives the CDDP complex good dissolvability. When dissolved in an aqueous medium, the CDDP is protected by a hydrophilic polyethylene glycol chain segment and a hydrophobic amino acid chain segment, which can effectively avoid a sudden release of the CDDP due to the influence of the blood circulation system after intravenous injection, thus improving the stability of the CDDP complex. A carboxyl group contained in the CDDP complex has pH value sensitivity and tends to be deprotonated in a low pH environment, which is advantageous for promoting the release of a drug, and improving the efficiency of the drug.
