The research was carried out to reveal the effect of Web2.0 supported geometry activities on the geometry skills of kindergarten children. The study group of the research consisted of 61-66 months old children with normal development who attended the kindergartens affiliated to the Ministry of National Education in Aydin in the 2022-2023 academic year. A total of 43 children were included in the study. In the study, a quasi-experimental design with pre-test/post-test control group was used to examine the effect of Web2.0 supported geometry activities on children's geometry skills. The data of the study were obtained by using the "Early Geometry Skills Test" developed by Sezer and Güven (2016) to determine the geometry skills of children and whose validity and reliability study was conducted. Web2.0 supported geometry activities were applied to the experimental group for a total of 10 weeks. On the other hand, the mathematics-based Ministry of Education program was applied to the control group. As a result of the research, when the mean scores of the children in the experimental and control groups regarding geometry skills were examined, it was determined that the applied Web2.0 supported geometry activities were effective in favor of the experimental group.