AbstractPolarographic behavior of 2,4-dinitrobenzene and products of its reduction, 2-chloro-5-nitroaniline and 4-chloro-3-nitroaniline, is studied: it is shown that formation of the corresponding chloronitroanilines in the case of polarographic reduction of 2,4-dinitrochlorobenzene is rather problematic. 0.1 M NaOH is recommended as the supporting solution for analytical control of conversion of 2,4-dinitrochlorobenzene and a mixture of 2-chloro-5-nitroaniline and 4-chloro-3-nitroaniline in reaction solutions obtained by preparative electroreduction of 2,4-dinitrochlorobenzene.