The Moroccan olive oil sector produces large volumes of olive mill wastewater (OMW), a highly polluting effluent rich in polyphenols and organic load (chemical oxygen demand: COD). This study explores an integrated solution using Microbial Fuel Cells (MFCs) to simultaneously remediate OMW and generate bioelectricity. We investigated how initial phenolic concentration influences bioelectrochemical performance using two distinct OMW samples (OMW1 and OMW4). Remarkably, power densities reached 1028 mW.m⁻³ and 1200 mW.m⁻³ , respectively. Corresponding phenolic reductions were 56% for OMW1(1 g L⁻¹ and 0.438 g L⁻¹ as initial,final concentrations respectively) and 70% for OMW4(4 g L⁻¹ and 1.186 g L⁻¹ as initial,final concentrations respectively), while COD removal achieved 52% and 76%, highlighting a direct link between substrate richness and system efficiency. Additionally, MFCs demonstrated substantial heavy metal removal (30–97%), confirming their multifunctional potential. These findings underscore the capacity of MFCs to convert a high-impact pollutant into renewable energy, offering a sustainable pathway for olive industry waste management in Mediterranean regions.The originality of the present study is based,firstly,on the systematic comparative investigation of two OMW samples in MFC treatment.Thereby, the impact of the complex OMW matrix, especially that of inhibitory phenolic compounds, is effectively decoupled from the system performance. Secondly,bioelectrochemical performance(delivering high power densities,COD and heavy metals removal rates) was reached in a short experimental time(5 days).