Introduction. Powder represents a solid pharmaceutical form, which according to its composition, can be simple (has only one active pharmaceutical ingredient (API)) and compound (has more than one API). To ensure optimal stability and pharmacokinetics of APIs, excipients (E) are added to the powders as the diluents, lubricants, glidants, sweeteners, stabilizers. The aim of the work. Evaluation of technological parameters for Es and their mixtures in combination with APIs at the stage of the powders preformulation. Material and methods. Individual Es such as: microcrystalline cellulose, lactose monohydrate, d-mannitol (Cel.; Lact.; Himedia), citric acid (Chem-Lab), saccharin (Zah.; SigmaAldrich) were used; model M1-M12 mixtures of E and combinations of E with APIs (potassium aspartate, magnesium aspartate and potassium orotate (Sigma-Aldrich) and spironolactone, (Acros Organic)) were prepared; RADWAG analytical electronic balance, ERWEKA tapped density tester, VP12A powder flow speed tester were employed. Results. Mechanical mixtures of Es without APIs and with them were prepared according to the technological rules of powder preparation and analyzed in terms of the basic technological parameters, the values of which should not exceed the established limits: Carr’s Index (<26%), Hausner’s Ratio (<1.35), Angle of repose (<350), Flow speed (<100g/25s). Following the conducted research, those combinations of model mixtures, corresponding to these established limits for the technological parameters: M3 (SA23.6%, Cel-50%, Lact-16.4%, Zah-10%), M5 (SA-23.6%, Cel-66.4%, Zah-10%), M8 (SA23.6%, Cel-50%, Lact-26.4%,) were analyzed. Conclusions. Following these studies, the technologically optimal Es for the formulation of the compound powders were selected and three formulations were chosen, which will be used for the next stages of analysis.