Electrochemical behavior of naphthalene 1-nitro-6-sulfonic acid was studied by polarography, voltammetry on glassy carbon electrodes, and electrolysis at controlled potential and in galvanostatic mode. The 1-nitro-6-sulfonic acid, like α-nitronaphthalene and naphthalene 1-nitro-3,6,8-trisulphonic acid, was shown to be polarographically reduced in a strong acidic medium in the presence of 0.1 N H2SO4 to the corresponding naphthalene aminosulfonic acid in a single six-electron stage via an intermediate formation of hydroxylamine. Deceleration of the 1-nitro-6-sulfonic acid polarographic reduction manifesting itself as a decrease of the polarographic current, as well as strong dependence of the polarization curves’ parameters and shape on the neutral and alkaline supporting solution composition and pH, are related to anionic character of the species being reduced, which is caused by the presence of acidic sulfonic group in their molecules. The technological parameters for the naphthalene 1-amino-6-sulfonic acid preparative electrosynthesis are determined: the current density 5–10 A/dm2, temperature 30–32°C, and concentration of the initial nitro-compound 10–13%, which provide the target product yield of 87.0–93.5%, the current efficiency of 38.0–42.4%, and recovery of 69.0–80.0% (on the N3 grade nickel and Kh18N10Т-stainless-steel cathodes in ammonia buffer solutions with pH 7.0–8.2). To increase the electroreduction efficiency of the nitro-Cleve’s acids’ technical isomeric mixture reduction, the mixture preliminary purification and the using of inert atmosphere are recommended in the processes of both electrolysis and the target Cleve’s-acid extraction from the solution.