The oxidative polymerization of 3,6-dianiline-2,5-dichlorobenzoquinone is studied for the first time and it is shown that its reactivity in oxidation processes is higher than that of aniline. The influence of concentration, reagent ratio, and the acidity and temperature of reaction solution on the oxidation reaction is investigated. The specific features of polymerization of 3,6-dianiline-2,5-dichlorobenzoquinone determined by the presence of a chloranil substituent at the nitrogen atom are revealed. Poly(3,6-dianiline-2,5-dichlorobenzoquinone) has a highly ordered supramolecular structure. The copolymerization of 3,6-dianiline-2,5-dichlorobenzoquinone with aniline is studied, and it is found that the reaction kinetics and the degree of copolymer oxidation are determined by aniline content in the monomer mixture.