Excessive usage of pesticides for the last several decades resulted in their bioaccumulation in the environment and thus presenting growing threat to humans and ecosystem. In order to remove the remains of pesticides from wastewaters and soil, different methods are being developed, whereas advanced procedures of photocatalytic degradations become more and more important. This work studied photocatalytic activity of new composite photocatalysts TiO2-SBA-15 and TiO2-MCM-41. Their photoactivity was compared to the activity of the initial mesoporous materials SBA-15 and MCM-41 that did not contain TiO2. TiO2 represents ordinary semiconductor material that is used for photocatalytic degradation. Photocatalytic degradation was performed in batch reactor with photocatalyst suspended in the reaction mixture. Pen-Ray lamp was used as a radiation source for photocatalytic degradation. Measurements were conducted at the constant initial imidacloprid concentration of 10 ppm. The reaction was observed by measuring conversion of imidacloprid at certain time intervals, and high performance liquid chromatography (HPLC) was used for that purpose. Experimental measurements included the changes in pH, in concentration of dissolved oxygen, and in changes of total organic carbon at the beginning and after the photocatalytic degradation. The results showed that the degradation of imidacloprid is possible only with application of TiO2 catalyst and adequate radiation source (UVA in this case). Mesoporous material MCM- 41 proved to be more efficient than SBA-15. In the final part of the test, the achieved experimental results were tested on the batch reactor model with the kinetic model for firstorder reaction, and the reaction rate constants, k, and the root mean square deviation, SD, were determined.