Water is considered one of the most important components of life. In recent years, the problem of pollution of water sources by pharmaceutical compounds of various groups and their metabolites has become an urgent problem all over the world. They can have significant adverse effects on the aquatic environment. At present, to make efforts to remediate and minimize traditional pollutants in the environment, other compounds of “emerging” concern (CECs) are now warranting attention. These compounds, although there are not very persistent, their continuous influx in the environment renders them pseudo-persistent and their “emerging” environmental issue is that they have been proved to be more than sufficient in inducing antibiotic resistance. Thus, advanced oxidation processes (AOPs) are recommended for wastewater pre-treatment or tertiary treatment, when wastewater contaminants have high chemical stability and/or low biodegradability. Among different AOPs, heterogeneous photocatalysis employing nanosize TiO2 has been an attractive research and development subject in water/wastewater treatment owing to its proven capability in the degradation of biorecalcitrant organic contaminants. The main goal of this work was to study the degradation/mineralization of a drugs mixture (amoxicillin, cephalexin and diclofenac) by applying heterogeneous oxidation with titanium dioxide. For each analysed systems, some physicochemical parameters have been optimized and the kinetic regularities of the transformation of pollutant oxidation processes have been studied. Degradation of drugs mixture (30 mg/L) by photocatalytic oxidation in the TiO2/H2O2/UV system with the aim of splitting benzene rings and turning substrates into simpler compounds depends on several parameters, such us: concentrations of oxidant (hydrogen peroxide) and catalyst dosage (titanium dioxide), temperature, reaction time, and рН value. As a result of laboratory studies, the oxidation conditions are optimized depending on the oxidant and catalyst concentration, wavelength irradiation for heterogeneous photocatalysis. It is presented that increasing the concentration of H2O2 to a certain level increases the concentration of OH radicals, which contribute to further degradation and increase efficiency. However, as the H2O2 concentration increases further, the oxidation efficiency begins to decrease as excess H2O2 can react with the OH radicals present to form water and oxygen. Based on the obtained results, it was found that the studied oxidation processes are very effective for treatment wastewater containing various pharmaceutical pollutants. The oxidation/mineralization in almost all cases reaches over 80% during first 10 min when substrate concentrations was 30 mg/L, H2O2 concentration - 1.5 mM/L, and catalyst dosage - 0.05 g/L for irradiation with UV-C rays.