Simultaneous electro-transfer of vanadium slag (V-slag) and electrochemical degradation of corncob lignin between two graphite electrodes in sulfuric acid solution were proposed. The electrochemical performance of V-slag dissolved by sulfuric acid solution on the graphite electrode was tested by cyclic voltammetry (CV) and linear polarization (LP) curves. By electrochemical transfer of Fe2+/Fe3+ and VO2+/VO2 + couple, it was found that iron and vanadium in V-slag played an important role in electrocatalysis. SEM, EDS and FT-IR were conducted to characterize the morphology, surface composition and the functional groups of lignin residues. By the inductively coupled plasma spectrometer (ICP) analysis, the cumulative removal rates of Fe and V in V-slag could reach up to 61.3% and 52.6%, respectively after multi rounds reaction. 30 kinds of compounds were identified in the process of degradation via GC–MS analysis. These results provided a new process for valorizing two widespread waste materials, V-slag and corncob lignin.