Novel branch-trunk Ag hierarchical nanostructures were fabricated by hydrothermal process combined with microwave-assisted synthesis. Te nanowires prepared by hydrothermal process were used as template. And then the branch-truck Ag hierarchical nanostructures were constructed on Te nanowires via galvanic replacement reaction with the Te nanowires as the sacrifice temple with microwave-assisted synthesis method. We further investigated the potential application of the obtained hierarchical nanostructures as sensors for the electro-chemical analysis of ascorbic acid. Results showed that the as-prepared sensors had a wide linear range of 0.17 mu M to 1.80 mM (R = 0.999) and a detection limit of approximately 0.06 mu M (S/N = 3). These indicated that the branch-trunk Ag hierarchical nanostructures were excellent candidate materials for sensing applications.