<p>Cu-metal organic framework (MOF) derived porous carbon (Cu/Cu₂O@C₇₀₀) derived from Cu-based MOF was prepared by one-step pyrolysis, and then used together with nitrogen-doped longan shell carbon (NCs) to establish a new electrochemical sensor for the rapid detection of enrofloxacin (ENR) by differential pulse voltammetry. The materials and the preparation process of electrochemical sensor were characterized. Results have shown that Cu/Cu₂O@C₇₀₀ exhibited abundant porous structures, high surface area, and numerous active sites, which significantly improved response sensitivity. NCs is a porous carbon material which possess high specific surface area and make the diffusion and transport of electrolyte ions easier. Under optimal conditions, the peak current of ENR exhibits favorable linear relationships with the concentration within a range 0.1–1000 ng mL^− 1, and the detection limit is 7.73 × 10^− 3 ng mL⁻¹ (S/<i>N</i> = 3). The sensor has good selectivity, stability and repeatability, and good recovery (93.90 ~ 104.0%, RSD&lt;4%) for the detection of ENR in fresh fish and shrimp. Compared with LC-MS/MS, it also shows competitive accuracy, which is of great significance in ensuring the safety of aquatic products.</p> Graphical abstract <p></p>