OBJECTIVES: To research and assess the frequency of occurrence of flat feet in students of Blaž Tadijanović Elementary School. STUDY DESIGN: A cross- sectional study. PARTICIPANTS AND METHODS: The target group of respondents were the students of the first three grades of Blaž Tadijanović Elementary School. Out of a total of 41 respondents, 25 boys and 16 girls aged seven and eight participated in the research. The research was conducted in accordance with the Code of Ethics for research with children using the plantogram method. Statistical analysis was done by testing the data with the t-test for independent samples, which shows the differences between the numerical variables of the two groups. RESULTS: The research found that out of the total number of respondents, 31 or 75.6 % of children have flat feet. 24.4 % of respondents have a normal foot shape. Out of a total of 31 children with flat feet, more than half, that is, 21 of them (67.7 %) have first degree flat feet. The frequency of the other two degrees is below 20 %. Boys have a significantly higher frequency of third (3 out of 18, i.e. 16.7 %) degree of flat feet. Descriptive analysis of the data showed a higher frequency of flat feet in girls (81.3 %) compared to boys (72.0 %), but the statistical t-test (t=0.7832, df=8) did not reveal a statistically significant difference (P=0.4815). CONCLUSION: The obtained results indicate a high frequency of flat foot deformity in the subjects. The most common form of deformity, observed in the subjects, is the first degree, which is considered favorable for correction with the implementation of therapeutic procedures. It is important to detect the symptoms in a timely manner, treat or prevent the occurrence of flat foot deformity, which as such causes many health problems at an older age.