A square-wave voltammetric method for the determination of kresoxim-methyl in grape juices was developed using the nanocrystalline boron-doped diamond electrode where an irreversible oxidation occurred. Measurements were made through the anodic scan from +1000 to +1750 mV (Maximum at +1420 mV) in pH 4.0 acetate buffer 0.050 mol L-1. Linear signal response (R-2 > 0.999) expanded form the 8.7 x 10(-7) mol L-1 (0.27 mg L-1) up to 3.4 x 10(-5) mol L-1 (11 mg L-1). The method was applied in the analysis of analyte fortified grape juices. Solid phase extraction allowed pre-concentration of the analyte and eliminated interferences imposed by sample matrix. Recoveries from 91.6% to 105.3% were found and agreed with results achieved using high performance liquid chromatography. (C) 2013 Elsevier B.V. All rights reserved.