Background: Throughout the coronavirus disease (COVID-19) pandemic, it is critically important to determine the prevalence of SARS-CoV-2 infection among the community to evaluate the success of the infection control policy. Despite the continually updated prevalence of COVID-19 worldwide and in Indonesia, testing is mainly focused only on symptomatic individuals.Objective: We aimed to determine the prevalence of COVID-19 in children and adults among asymptomatic population in Medan, North Sumatera Province, Indonesia.Methods: We conducted a cross-sectional study to assess prevalence of COVID-19 in different districts in Medan City, North Sumatera Province, Indonesia from 24 November 2020 to 12 January 2021. Nasopharyngeal swab specimen was collected from individuals and transported to Microbiology laboratory at Faculty of Medicine of Universitas Sumatera Utara. Detection of either E, N, and ORF1ab gene was used to confirm the presence of infection. Data on age, sex, occupation, and district of residency were analyzed.Results: A total of 2020 individuals were screened during the study period. Of those, 122 (6.0%) were positive for COVID-19. The positivity rate ranges from 0,6% to 31.7% at nine different locations of mass screening. 652 children were being tested and 9% (11) of children contributed to all confirmed cases. All of the children were asymptomatic.Conclusion: Although, children tend to be asymptomatic and less infected compare to other groups of age. Yet, their status of infection is particularly crucial since they still can be a source of COVID-19 infection to parents, caregivers, teachers, and the elderly.