A procedure for the simantenous determination of aminotriazole, triazolopyrimidinone and nirotriazolopyrimidinone was developed using the HPLC method with UV detection. To achieve the best chromatographic characteristics, it is proposed to use a column with a grafted aminophase Zorbax NH2 (Agilent Technologies, USA). The possibility of applying the developed methodology for the technological control of the second stage of the drug «Triazid» preparation is established following the results of the validation.