4, 5-Diaminochrysazin was prepared from chrysazin by ethylation and nitration followed by reaction with hydroiodic acid (HI). Treatment of 1, 8-diethoxy-4, 5-dinitroanthraquinone with HI resulted not only in O-deethylation, but also in reduction of nitro groups with more than 95% yield. This is a unique finding and is reported for the first time with a definite improvement over literature methods and is suitable for scale-up.