There are a wide range of diseases that are specific to children only (including some infectious diseases). This work presents the most common contagious diseases of pre-school children today, and each disease is individually described with regard to its clinical picture, symptoms, treatment, diagnosis. Some of the most common diseases are rubella, measles, watermelon, etc. Obviously, that it is an infectious disease, prevention makes it one of the main items to suppress the infection and illness itself. It is therefore of great importance that parents and educators know as much as these diseases and are able to differentiate the condition of a sick and healthy child. There are a number of preventive measures in medicine, and preventive measures in kindergartens are: maintenance of personal hygiene, regular maintenance of cleanliness of all premises and equipment with the prescribed disinfection of used objects and surfaces, systematic medical examination of children entering nursery, absenteeism in kindergarten due to illness, anti-epidemic measures in case of contagious disease, health education in kindergarten, as well as parents and adopters of children, isolation of patients, vaccination against infectious diseases. Although recent opinions of parents about vaccination are divided, it is certainly one of the most effective ways to combat contagious diseases and the overall protection of the human population.