In this paper, we investigated the rate of degradation of organic dyes across zinc oxide (ZnO) nanoparticles using photocatalysis. This research has shown that there is an environmentally friendly way to decompose industrial organic dyes released into the environment through wastewater. Zinc oxide is a biologically and environmentally friendly non-invasive material with relatively fast decay time, and it being one of the best choices as a catalyst for decay of industrial paints. The idea is that nanoparticles discharged into wastewater would assist photocatalysts in the decay of industrial dyes through the natural UV rays. ZnO nanoparticles were synthesized by laser ablation in the liquid. The resulting colloidal solutions were analyzed by us using spectrophotometers to obtain the wavelength dependences of absorbance. With the help of dependency, we made a Tauc graph from which we calculated the energy gap between water and valence bands of zinc oxide. We studied the obtained nanoparticle samples and used a scanning electron microscope (SEM) to determine their shape, diameter, morphology and size distributions. In order to calculate the number and increase the concentration of nanoparticles in individual samples, we used laser ablation and, using light microscopes, calculated the volumes of craters formed after. We calculated the volume of the crater by determining the circular surfaces of the crater at different depths, calculating the volumes of the truncated cones where the bases of these cones were the surfaces of the crater, and summing the volumes of the truncated cones to obtain the final volume of the crater. The volume of the crater corresponds to the volume of ablated material, that is, the total volume of nanoparticles from which the destination is determined, and which is the total mass in the colloidal solution. The wells of the ZnO nanoparticle solution were partitioned into samples of different numerical concentrations and added industrial dyes to the individual samples. These samples were re-analyzed with a spectrophotometer to obtain a greater dependence of the wavelength absorption. Subsequently, the samples were treated with UV and VIS mercury lamps every 10 minutes between which we performed spectrophotometry each time.