A new, simple, rapid, and inexpensive voltammetric method for the determination of a novel fungicide, fludioxonil (Flu), was firstly developed using square wave voltammetry (SWV). This was based on its electrochemical cathodic reduction at about -1.1V vs. an Ag/AgCl/KCl reference electrode in citrate-phosphate (C-P) buffer (pH 3.7) on a renewable silver amalgam film electrode (Hg(Ag) FE). To select the optimum experimental conditions, the effect of the supporting electrolyte, pH, conditioning potential and conditioning time, frequency, amplitude, step potential, and equilibration time were studied. Under optimized conditions, the proposed method exhibited acceptable analytical performances in terms of linearity (over a concentration range from 2.00 x 10(-6) to 2.25 x 10(-5) mol L-1), the detection limit (LOD = 5.81 x 10(-7) mol L-1) and the quantification limit (LOQ = 1.94 x 10(-6) mol L-1) for a solution containing Flu. The validation of the method was carried out. The developed procedure was successfully applied to determine Flu in the spiked Warta River water samples. To understand the Flu electrode mechanism, the cyclic voltammetry (CV) technique was applied. The reduction mechanism was also confirmed using mass spectrometry with the electrospray ionization (ESI-MS) technique. The influence of Flu on the corrosion properties of stainless steels used to produce agricultural tools were investigated using electrochemical techniques. (C) 2015 Elsevier Ltd. All rights reserved.