Objectives:Exposure to second-hand smoke (SHS) is widespread in restaurants in Ulaanbaatar, the capital city of Mongolia. While a smoke-free policy is the most effective way of protecting restaurant workers and customers from SHS, this has not been well accepted in Mongolia. Furthermore, little is known about restaurants’ attitude toward the smoke-free policy.Methods:A cross-sectional survey directed to restaurant owners or managers was conducted in 475 representative restaurants in Ulaanbaatar. Face-to-face interviews using a questionnaire and on-site observation were performed.Results:Only 29.3% of the restaurants claimed to prohibit smoking; none of the remaining had any protection toward SHS, and half of the restaurants estimated that more than 20% of customers would smoke inside. None of them had visible “no smoking” signs and the majority never received complaints about SHS. Despite the generally high level of knowledge of the health effects of SHS, of the 336 restaurants that were not smoke free, only 25.9% expressed that they planned to take action in the near future. By contrast, 87.8% of restaurants would support the government if it asked all restaurants to ban smoking. Multivariate analysis identified that restaurants having menus in foreign languages, selling cigarettes and predicting business decline were less likely to support the government smoke-free policy.Conclusions:This survey demonstrates that restaurants owners and managers were reluctant to take action on their own, but would support government policy. The government can assume a stronger role first by revising the law on tobacco control following the Framework Convention on Tobacco Control guideline.