Herein, we report a facile solvothermal assisted synthesis of reduced graphene oxide (rGO) supported niobium pentoxide (Nb2O5) nanosphere modified glassy carbon electrode (rGO-Nb2O5/GCE) sensor for the detection of persistent organic pollutants (POPs) like bisphenol A (BPA) and hydrazine (Hy). The as-fabricated sensor exhibits high sensitivity, selectivity and a wide dynamic range of detection from 10~μ M to 300~μ M for BPA, at a low electro-oxidation potential of 0.3 V with a sensitivity of 0.153~μ A/μ M.cm2 and limit of detection (LOD) of 0.295~μ M. Similarly, the sensor exhibits a wide dynamic range of detection from 10 nM to 50~μ M under a low electro-oxidation potential of 0.2 V with a low LOD of 2.709 nM and a sensitivity of 11.5~μ A/μ M.cm2 for Hy. Additionally, the sensor is found successful in sensing the BPA and Hy in drinking water and tap water samples. The excellent performance of the rGO-Nb2O5/GCE sensor can be attributed to the synergistic effect of rGO, providing excellent electrical conductivity and the Nb2O5 providing high electrostatic adsorption of the analyte via Nb4+/Nb5+ redox couple favouring electrooxidation process at the surface of the electrode. This proves the as-fabricated sensor as an ideal platform for developing simple electrochemical sensors for numerous bioanalytical applications. © 2001-2012 IEEE.