INTRODUCTION: Second-hand smoke is associated with more than 1.2 million deaths per year among non-smokers. Smoking in public places is prohibited in The Gambia but there is no information on the level of exposure to second-hand smoke among adolescents and adults 15-64 years. The aim of this study was to assess the level and predictors of exposure to second-hand smoke in public places and compliance with smoke-free regulations in The Gambia. METHODS: A population-based survey was conducted in an established Health and Demographic Surveillance System (HDSS). A total of 4547 participants (15-64 years) from households within the Farafenni HDSS were interviewed at their homes but only 3343 were included in our analysis. Factors associated with exposure to second-hand smoke in public places were assessed by three different multivariable regression models. RESULTS: Exposure to tobacco smoke in public places was high (66.1%), and higher in men (79.9%) than women (58.7%). Besides being male, less education, lower household income, urban residence and not aware of smoke-free regulations were strongly associated with exposure to second-hand smoke. CONCLUSION: Despite existing smoke-free regulations, reported exposure to second-hand smoke remains high in public places in The Gambia. The Ministry of Health should continue to strengthen their advocacy and sensitization programs to ensure smoke-free regulations are fully implemented. Some population subgroups are at a higher risk of exposure and could be targeted by interventions; and settings where these subgroups are exposed should be targeted by enforcement efforts.