Wastewater treatment plants mostly use the conventional biological method with activated sludge for wastewater treatment. However, activated sludge itself becomes the output of such wastewater treatment which has to be appropriated disposed of. Therefore, it should be analyzed before disposal. In this case, we will monitor pesticides (acetamiprid, clothianidin, thiacloprid) in activated sludge by chromatographic method after solvent extraction. Namely, despite frequent opposition to the use of pesticides, they are still produced and used in large quantities, including these investigated pesticides. Therefore, it is necessary to monitor them not only in the environment but also in samples such as activated sludge. In this paper, the method of extraction by matrix solid-phase dispersion (MSPD) was used for extracting the mixture of pesticides from activated sludge. Analysis of the extracts was performed by high performance liquid chromatography with a diode array detector (HPLC-DAD). The parameters of MSPD extraction that have been optimized are sorbent type, activated sludge to sorbent mass ratio and the solvent or mixture of solvents for elution. The best results were obtained using egg shells with a mass ratio of activated sludge to egg shells 1:1 and 1:7 and methanol as a elution solvent.