Heterogeneous photo-Fenton oxidation of organic compounds is an advanced oxidation process in wastewater treatment allowing to overcome the main drawbacks of homogeneous photo-Fenton process. In this work we compare the performances of honeycomb monolith structured catalysts based on LaMeO3 perovskites (Me = Mn, Fe) for the photo-Fenton oxidation of acetic acid. Nanosized supported perovskites, in the absence or in the presence of Pt nanoparticles well anchored to a “macroscopic” monolithic support, allow the total oxidation of acetic acid. Controlled dosing of H2O2 to the process is a critical issue to obtain the fast and efficient oxidation of several organic compounds, such as methyl tert-butyl ether, methanol, ethanol to CO2 and H2O. The treatment of a synthetic winery wastewater was also successfully investigated.