The paper presents the results of field tests the aim of which was to assess the effect of microbiological preparations (Azofix, Fosfix, Maxproline) on yielding the cultivar of maize cultivated in stubble aftercrop. The microbiological preparations were applied before maize sowing and in the phase of 4-5 leaves. In order to verify the adopted assumptions, the dynamics of the initial growth and the yield of fresh and dry matter were determined. There was shown that the applied microbiological preparations increased the dynamics of the initial growth of maize sown in stubble aftercrop. The use of microbiological formulations in maize cultivation in stubble aftercrop caused an increase in dry matter yield in relation to the exclusive mineral NPK fertilization from 14,2% to 33,3%. Only the Azofix + Fosfix + Maxproline application resulted in a reduction in the dry matter yield of maize by 4,8%. With the exception of Azofix, the foliar application of the remaining microbiological preparations was more effective compared to the soil application.