  We apply the fidelity approach to study the topological superconductivity in
a spin-orbit coupled nanowire system. The wire is modeled as a one layer
lattice chain with Zeeman energy and spin-orbit coupling, which is in proximity
to a multi layer superconductor. In particular, we study the effects of
disorders and find that the fidelity susceptibility show multiple peaks. It is
revealed that the major peak indicates the topological quantum phase
transition, while other peaks signal the pining of the Majorana bound states by
disorders.
