Schools are an important arena for smoking prevention. In many countries, smoking rates have been reduced among adolescents, but the use of smokeless tobacco is on the rise in some of these countries. We aimed to study the associations between schools' restrictions on smoking and snus and on the use of these tobacco products among students in upper secondary school. We employed data from a national representative study of 1444 Norwegian students, aged 16-20 years. Respondents were asked about their schools' restrictions on snus and smoking and own use of these products. We examined associations between restrictions and the use, controlling for age, gender, type of school and regional differences. We found clear consistent associations between schools' restrictions on tobacco use and less use of these products. More explicit pervasive restrictions were strongly associated with the prevalence of use. This first study on the associations between schools' restrictions on snus and the prevalence of snus use corroborate what has been found in many studies on smoking restrictions and smoking. Strict school tobacco policies may be an important tool if health authorities are interested in implementing measures to limit or reduce snus use among adolescents.