Purpose: The aim of the present study was to assess the prevalence, distribution and sociodemographic factors associated with tooth wear among Sri Lankan adolescents. Materials and Methods: A total of 1200 17-year-olds were selected from government, private and international schools in the Colombo district of Sri Lanka using a two-stage cluster sampling technique. The data were collected using a pretested, validated self-administered questionnaire and by conducting a clinical examination. Tooth wear was recorded using a modified version of Smith and Knight's tooth wear index. Results: The prevalence of tooth wear among Sri Lankan adolescents was found to be 22.4%. In nearly 13.7%, tooth wear was confined to the enamel, whereas 8.7% had wear lesions extending up to the dentine. Occlusal surface was the most frequently affected surface, while the first molar was the most frequently affected tooth. Tooth wear was significantly associated with the type of school attended, father's occupational status and mother's level of education. Conclusions: The present study found that nearly one-fourth of the adolescents were affected by tooth wear. These findings are in agreement with those from developed countries where tooth wear has been shown to be an emerging oral health problem. Keywords: adolescents, prevalence, tooth wear