Pecan-kernel-like TiO₂ hierarchical architectures and Au-loaded TiO₂ were successfully synthesized via facile hydrothermal synthesis method and simple precipitation route. A series of material characterization methods were employed to characterize the structure, morphology of as-synthesized materials. Characterization indicate that uniform and independent pecan-kernel-like TiO₂ hierarchical architectures consisted by nanorods stacking were formed, and Au nanoparticles were distributed uniformly on the surface of TiO₂ materials. In addition, The gas sensing performance of the sensors based on pure TiO₂ and different amounts of Au-loaded TiO₂ were systematically investigated. The noble metal Au improved the catalytic efficiency which played crucial role in enhancing the performance of the gas sensor. The results indicated that the sensor with 5 wt% Au-loaded TiO₂ exhibited the highest response, short response/recovery time, excellent repeatability and stability to toluene.