A process for preparing 1-aminoanthraquinone, comprising the steps of:A. reacting o-chloromethylphenylisocyanate with at least an equivalent amount of benzene in anhydrous hydrofluoric acid at a temperature of about -10.degree. to 200.degree. C to form the lactam of 2-amino-diphenylmethane-2'-carboxylic acid,B. saponifying the lactam of 2-amino-diphenylmethane-2'-carboxylic acid with aqueous alkali at a temperature above about 100.degree. C to form the 2-amino-diphenylmethane-2'-carboxylic acid,C. contacting the 2-amino-diphenylmethane-2'-carboxylic acid with an acid condensation agent, thereby to convert the carboxylic acid to 4-amino-anthrone, andD. contacting the 4-aminoanthrone with an oxidizing agent in an acid or alkaline medium, thereby to convert the aminoanthrone to 1-aminoanthraquinone. Special conditions are also recited for carrying out the individual steps to obtain high yields.