This work focused on the application of an advanced oxidation process (AOP) such as ozonation in soils with sandy texture and little organic matter, contaminated with the pesticides lindane and DDT. The O3 flux was applied in triplicates for each treatment, with the independent variables: Dry Soil or Wet Soil, and ozone treatment time (0.012 g per minute) of 30min and 60min (each treatment with its respective control). The results showed a decrease of 30.72% of DDT and 26.24% of lindane corresponding to the 60-minute dry soil treatment. A previous analysis of soil organic matter showed a 70% decrease in relation to the control, in dry soil. In a test on the biological activity of soils subjected to the treatments: contaminated soil treated with ozone and decontaminated soil inoculated with non-contaminated soil extract, the results reveal that non-contaminated and contaminated soils showed normal microbial activity, with differences in dynamics, and visible adaptation and selection phases in those subjected to ozone treatment. Basal respiration and metabolic quotient qCO2 values were also obtained, showing an increase in the ozone and re-inoculated soil treatments, in which a certain degree of stress can be observed.