OBJECTIVE The aim of this study is to examine the prevalence of selective mutism (SM) in Kocaeli, Turkey. METHOD Kindergarten, first, second and third grade students of all public/private schools within the city were included in the study. "SM screening forms" prepared on basis of DSM-IV were submitted to classroom teachers in all these schools asking whether they had any students meeting such symptoms. RESULTS About 84.51% of the schools returned forms covering 64,103 children. Five hundred and twenty six of these children were thought to have symptoms of SM by their teachers. After their DSM-IV based clinical evaluation by a child and adolescent psychiatrist, only 21 children were diagnosed as SM. Among the SM group, three were in the kindergarten, 15 were in the first grade and three were in the second grade. Twelve of the children were male and nine were female (male: female ratio is 1.3:1). In this cross-sectional study, 0.83% of children were reported to have SM symptoms by their teachers. After the clinical evaluation of these children, the prevalence rate of SM was found to be 0.033%.