Pesticides are the most perilous organic compounds that are of major human health concern. The hazardous pesticides such as bentazone (BTZN) and mexacarbate (MCBT) which badly cause the environmental pollution and pose lethal impacts on human health. In an effort to develop a highly efficient, reliable and sensitive electrochemical sensor, the novel CuO nanostructures were synthesized through easy and green aqueous chemical growth procedure and used as sensitive probe for the simultaneous determination of bentazone and mexacarbate pesticides. The prepared material was used as conductive and catalytic tool for the modification of glassy carbon electrode (GCE). The exquisite CuO nanostructures were characterized by FTIR, FE-SEM, XRD, EDS, zeta sizer and zeta potential to reveal the functionalities, morphological texture, crystallinity, size and existing charge on the surface of nanostructures. The conductive nature and charge transfer kinetics of CuO/GCE was explored through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under the optimized parameters, the sensitive and reliable simultaneous determination of two pesticides was carried out via CV and DPV that exhibited fluent determination process. The Ipa response was linearly proportional to the concentration of pesticides with low LOD and LOQ observed as (0.008 and 0.026 µM) for bentazone and (0.0015 and 0.004 µM) for mexacarbate, which is lower than the permissible limit set by US Health Advisory Level. Moreover, the developed sensor manifested tunable reusability, stability, and selectivity for both analytes. The proposed method is a reliable step towards the on-site detection of pesticides in various resources.