Down syndrome is a genetic disorder caused by the trisomy of chromosome 21, which is characterized by delays in the development of communication, language and speech. Repetitive behaviors are common in children with Down syndrome, but they are also an understudied phenomenon. The aim of this thesis is to research the occurrence of repetitive behaviors in children with Down syndrome in more detail. In addition to researching the frequency of different categories of repetitive behaviors, the goal is to also research the level of disturbance that these repetitive behaviors cause in everyday situations. The study used the Repetitive Behaviour Scale-Revised consisting of 6 subscales: a subscale of stereotypical sensory-motor behaviors, a subscale of self-injurious behaviors, a subscale of compulsive behaviors, a subscale of ritual behaviors, a subscale of sameness behaviors, and a subscale of restricted behaviors. The questionnaire was completed by parents of children with Down syndrome, and the sample consisted of 36 children (20 boys and 16 girls) between 2 and 7 years of age. Stereotypical sensory-motor behaviors have been shown to be by far the most commonly observed, and restricted and sameness behaviors also occur frequently, but to a much lesser extent. The results of the research confirm a higher level of disturbance in everyday situations, especially caused by behaviors belonging to the categories of stereotypical sensory-motor, sameness and self-injurious behaviors. This research is not enough to generalize these results, but the data obtained can be used in working with children with Down syndrome. Repetitive behaviors are often considered undesirable and detrimental to development due to a lack of understanding of their function. A better understanding of repetitive behaviors allows for a better understanding of the everyday challenges faced by children with Down syndrome, thus improving their quality of life.