Synthesis of gold nanoparticles(AuNPs) and Pluronic triblock copolymer composite in aqueous medium was studied.Gold-polymer nanocomposite with different structures was fabricated by tailoring the molar ratio of gold precursors to Pluronic P123 molecules or pH value of the P123 solution.When a lower volume ratio of [AuCl4-]/[P123](0.05) was employed at pH 11.1,a nanostructure similar to plum pudding was obtained.AuNPs with an average diameter of 13.1 nm were embedded in Pluronic assemblies,and each one held about 21 single gold nanoparticles.When [AuCl4-]/[P123] was increased to 0.1,core-shell structure was obtained if the pH value was in the range of 10.6～11.6,while gold polyhedra were fabricated when pH value was 8.1.Typical core-shell AuNPs had an average diameter of 9.6 nm with a narrow size distribution,while gold polyhedras with a mean diameter of 12.8 nm was obtained.The specific morphologies of the resultant nanocomposite were presumably obtained due to the synergistic interaction among the reactants. Synthesis of gold nanoparticles (AuNPs) and Pluronic triblock copolymer composite in aqueous medium was studied. Gold-polymer nanocomposite with different structures was fabricated by tailoring the molar ratio of gold precursors to Pluronic P123 molecules or pH value of the P123 solution. When a lower volume ratio of [AuCl4-] / [P123] (0.05) was employed at pH 11.1, a nanostructure similar to plum pudding was obtained. AuNPs with an average diameter of 13.1 nm were embedded in Pluronic assemblies, and each one held about 21 single core-shell structure was obtained if the pH value was in the range of 10.6 to 11.6 while gold polyhedra were fabricated when pH value was 8.1.Typical core- shell AuNPs had an average diameter of 9.6 nm with a narrow size distribution, while gold polyhedras with a mean diameter of 12.8 nm was obtained. The specific morphologies of the resultant nanocomposite were presumably obtained due to the synergistic interac tion among the reactants.