In this study, two different particle sizes of Au nanoparticles (NPs) were synthesized using two different stabilizers, and then two different morphologies Au@TiO2 hollow spheres were obtained when the corresponding Au NPs solutions were added to the TiF4 ethanol-water solution under hydrothermal condition. The computational simulation is employed to provide the fundamental support to explain why different stabilizers yield different sizes of Au NPs, and the main cause for the experimental observation is contributed by the different interactive forces between Au and stabilizer molecules. The experimental strategy adopted different stabilizer in this work is expected to be generally applicable for the synthesis of many other types of micro-nanostructured materials.