Influence of soil and postemergent herbicides in the technology of continuous corn growing on activity of biological processes in chernozem typical is studied. It has been shown that using herbicides for three years in a row in the system of corn protection caused decreasing the contest of total biomass of microorganisms in the soil by 8–57% compared to lealand and increasing the emission intensity of СО2 from the soil by 2–13% compared to control depending on chemical preparation type. Applying preparation Esteron 60 k.e. (consumption rate 80 l/ha) caused decreasing of total biomass of microorganisms by 42.1% and oxidoreductase activity by 19–20% compared to control, increasing soil phytotoxicity up to 56.5%. Spraying the crops with postemergent herbicides Milagro 040 SC k.c. and Kallisto 480 SK, KC at recommended consumption rate of (1.0 and 0.2 l/ha correspondingly) does not cause essential depression of soil microbiota and activity of ferments polyphenol oxydase and peroxydase. Soil phytotoxicity in these variants was at the level of 31.9 and 36.3% which was 9.6 and 24.7% higher than in control correspondingly. According to soil phytotoxicity indices in the technology of continuous corn growing researched herbicides are placed in such row: Milagro 040 SC k.c. < Kallisto 480 SC, KC < Stomp 330, k.e. < Harnes, k.e. < Dianat, BRK < Esteron 60 k.е.