  Work statistics characterizes important features of a non-equilibrium
thermodynamic process. But the calculation of the work statistics in an
arbitrary non-equilibrium process is usually a cumbersome task. In this work,
we study the work statistics in quantum systems by employing Feynman's
path-integral approach. We derive the analytical work distributions of two
prototype quantum systems. The results are proved to be equivalent to the
results obtained based on Schr\"{o}dinger's formalism. We also calculate the
work distributions in their classical counterparts by employing the
path-integral approach. Our study demonstrates the effectiveness of the
path-integral approach to the calculation of work statistics in both quantum
and classical thermodynamics, and brings important insights to the
understanding of the trajectory work in quantum systems.
