The aim of my Bachelor study was to describe various forms of disinfection of drinking water, and to analyze the disinfection process used in my hometown. In my work, I listed the different methods of disinfection of drinking water and I described the advantages and disadvantages of each of these methods. During my research, I found that the most widely used chemicals in the disinfection process are chlorine and its compounds. Another important method for water disinfection is ozonation. However it's use is not as common, because producing ozone is a difficult and very expensive process. The third process that I explored in my study is the UV ray method. This method doesn't involve chemicals in itself, but additional chlorine is used to assure maximal water quality, which is normally added after the UV radiation. The most notable problem of using UV rays is the short life-span of the UV lamps. In the last part of my work I described the water treatment methods used in my hometown, amongst which the usage of chlorine is the predominant.