This present study describes a pencil graphite electrode surface covered with Cu(II) and Fe(III) complexes based on Salophen derivative Schiff bases in acetonitrile solution containing LiClO4 as a supporting electrolyte. Cyclic voltammetry method was used for the surface modification procedure with 25 cycle at a sweep rate of 50 mV s−1. Some characterization methods were used to identify of the prepared modified surfaces including cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), Ultraviolet‐visible Spectroscopy (UV‐Vis), and Scanning Electron Microscopy/Energy Dispersive X‐ray Spectroscopy (SEM/SEM‐EDX). The catalytic activity of these modified surfaces on the electrochemical oxidation of catechol (CC) was investigated and they compared with each other. The results demonstrated that these modified electrodes showed perfect electrocatalytic activity on the catechol determination, however the modified electrode prepared with the Cu(II) complex has higher catalytic activity than this prepared with the Fe(III) complex thanks to its the lower detection limit.