We report for the first time on the elaboration of a remarkable sensitivity type C/p‐NiTSPc carbon fiber microelectrode (CFME) for p‐nitrophenol (PNP) pollutant. We observed the best performances using square wave voltammetry (SWV) technique in the place of differential pulse voltammetry (DPV). Also the combination of p‐NiTSPc optimized cycles of electrodeposition and accumulation time, helped us to increase remarkably the sensor slope (320 times) and the limit of detection (LOD)(1000 times), with a final LOD of 0.1 µg/L, the current regulatory limit for drinkable waters. Furthermore the recoveries of the standards added are close to 100% indicating that the method has some suitability. The proposed voltammetric procedure might be applied for organophosphorus pesticides and their by‐products with a remarkable sensing in natural polluted waters.