Previous studies among Buddhist monks in Thailand have reported smoking rates to be as high as 55%. Because 95% of Thais are Buddhist, monks are highly influential in establishing normative behavioral patterns. As the first population-based study on smoking among Buddhist monks in Thailand, this study aims to determine the smoking prevalence in six regions of the country, and to examine smoking knowledge, risk perceptions, behaviors, and associated demographics among full-fledged and novice monks (n = 6,213). Results demonstrated that the overall prevalence for current smoking monks is 24.4% (95% confidence interval [24.453, 24.464]), with regional differences ranging from 14.6% (North) to 40.5% (East). Findings suggest that integrating prevention and cessation programming into religious courses may be one avenue for reaching many incoming monks. Further, involving monks in tobacco control education and setting a nonsmoking standard among them is vital to the success of reducing smoking rates among the general population in Thailand.