One of the most important and first places where a child acquires social contacts as well as awareness of personal hygiene is kindergarten. Kindergartens must also meet hygienic and technical requirements, both indoors and outdoors children's playground. In addition to the standard equipment contained in the children's playground, many preschool institutions have sandboxes in their playgrounds and they can be a source of biological danger, as parasites (Echinococcus granulosus, Toxocara canum, Toxocara cati, Dipylidium canium) can be found in them. The aim of this paper is to present the analysis of sandboxes in preschool institutions, that is what health risks may occur, but also to discover possible causes of diseases in preschool institutions. In this paper, an example of an analysis performed in a kindergarten in the Primorsko-goranska County was taken. Two sandboxes of different sizes were analysed. Representative samples were taken at different sandbox sites under different weather conditions and environmental factors such as humidity, temperature, time of day, sun exposure were taken into account. After performing the analysis, the results indicate the presence of certain types of parasites in both sandboxes. In order to ensure the best possible conditions and condition of the sand, it is necessary to continuously conduct sampling at different times of the year and at different locations in the sandbox. Such research and preventive procedures achieve a quality and safe environment in preschool institutions.