A series of nanostructured Pd–Fe bimetallic thin films with the performance of fast and high-efficiency electrochemical reductive dechlorination were directly formed on glassy carbon electrodes (GCEs) through galvanic replacement of partial Fe 0 nanoparticles by Pd(II) ions. The composition and morphology of such Pd–Fe thin films are strongly dependent on the sacrificial Fe film templates fabricated by a template-free, double-potential step electrodeposition technique. The size, shape and morphology of the Fe nanoparticles that constitute the Fe thin films can be controlled well by adjusting the concentration of Fe 2+ ions in electrolyte solutions. Due to the good synergistic effect between Pd and Fe, the as-prepared Pd–Fe thin films with the novel microstructure display a high reactivity towards the electrochemical reductive dechlorination of carbon tetrachloride (CT), which closely related to the composition of Pd–Fe thin films, applied potential and temperature. The dechlorination reaction of CT complied with pseudo-first-order kinetics.