[en] The basic stages of the optimization of the multi-element quantitative activation analysis are discussed with the use of the multi-factor experimental design. Time of analysis is chosen to be the function of optimization. The range for which the function is defined designs. Time of analysis is chosen to be the function of optimization. The range for which the function is defined is specified by restrictions on the element determination limits. The effectiveness of the suggested method was tested upon the model problem of determination of Cl, Cr and Ba in O, Na, Cl, Cr, Ba matrices by γ-activation. Activations were performed in a betatron. As a monitor tablet BaF₂ was used with photopeak recording being 0.662 MeV. (T.I.)