FIELD : medicine.SUBSTANCE : invention refers to medicine, oncology and chemical engineering. Method of producing the technetium-99m complex with recombinant protein-targeted molecules for radionuclide diagnosis of oncological diseases with HER-2/neu overexpression consists in the fact, that at the first stage aquacarbonyl technetium-99m [99mTc(H2O)3(CO)3]+ is obtained, using sodium tetraborate sodium lyophilizate, decahydrate, sodium carbonate, disodium boron carbonate, which can also contain potassium sodium tartrate tetrahydrate or sodium citrate monohydrate, then lyophilisate is added with 1–3?ml sodium pertechnetate solution, 99mTc with activity of 0.74–3.7 GBq and heated in a boiling water bath for 20–30?minutes, cooled to room temperature and added with 1?M HCl to pH?7.4 or 300–900?mcl of 1?M sodium phosphate solution with pH?7.4, further, a chelating agent succinimid-1-yl 6-(bis(pyridin-2-ylmethyl)amino)hexanoate (DPAH) is added to DARPin in a phosphate buffer with pH 8.3-8.5 to obtain DPAH-DARPin, then aqua-carbonyl technetium-99 m [99mTc(H2O)3(CO)3]+ is bound with DARPin or DPAH-DARPin, for which to DARpin or DPAH-DARPin in amount of 100?mcg in a phosphate-buffer solution at pH?7.4 1?ml of aqua-carbonyl technetium-99m solution [99mTc(H2O)3(CO)3]+ is added, then incubated at 40?°C for 30–60?minutes, purification is carried out by gel filtration on a column.EFFECT : invention is aimed at radionuclide diagnosis of oncological diseases with HER-2/neu overexpression.1 cl, 12 ex