Cyclic and square wave voltammetric measurements were performed to deduce the electrochemical behavior of fomesafen herbicide on the prepared carbon nanotube paste electrodes. Fomesafen has created a well-defined cathodic peak at -540 mV (vs. Ag/AgCl), but no corresponding oxidation peak has appeared on the reverse scan. The influence of the pH on the electro-reduction peak was tested at various pH values, and the E (p) versus pH plot suggested that protons are involved in reduction process. Electrochemical studies showed that -NO2 group was responsible for the reduction process. A linear relationship has been constructed in the concentration range of 0.30-40 mg/L. The limits of detection and quantification values were obtained as 0.089 and 0.297 mg/L, respectively. Fomesafen was determined in the presence of some well-known pesticides, and the extent of recoveries of 5 mg/L fomesafen in the presence of equal amounts of pesticides anilazine, pymetrozine, and triflumizole was 103.7 +/- 0.9, 94.3 +/- 0.4, and 97.9 +/- 0.5 %, respectively (n = 3). The accuracy of the recommended method was further proved by the determination of fomesafen in spiked real samples such as apricot juice, cherry juice, and lake water with a relative error of -4.2, -2.8, and -1.8 %, respectively. The obtained results suggest that the recommended method is sufficiently accurate, selective, and precise.