Abstract: Objective To describe the prevalence of secondhand smoke(SHS) exposure among residents in Guangzhou city and to explore the association between SHS exposure and willingness to implement smoke-free regulation.Methods A cross-sectional survey was conducted in Guangzhou city using stratified multi-stage cluster sampling design.Totally 5 135 residents aged ≥15 years were administered a face-to-face interview and SHS exposure status in the residents of different demographical characteristics were compared.Correspondence analysis was used to examine the relationship between SHS exposure and willingness to implement smoke-free regulation.Results Among the 4 239 non-smokers,48.98% were male.SHS exposure was reported by 46.99% of respondents and the males were more likely to report exposure to SHS compared to the females(48.95% versus 45.98%,P>0.05).Participants with high school/technical secondary school or higher education(55.72%) and enterprise employees(54.34%) had significantly higher SHS exposure rate,while respondents aged 65 years and older(28.51%) and divorced/separated/widowed persons(23.60%) had significantly lower SHS exposure rate.SHS exposure was significantly associated with the awareness of smoke-free regulation and the willingness to implement the regulation.There was no significant association between SHS exposure and knowledge about smoking hazards.Correspondence analysis showed that awareness of and willingness to implement smoke-free regulation were related to without SHS exposure,but unwillingness to implement smoke-free regulation was related to SHS exposure of 1-3 days/week and the unawareness of smoke-free regulation was related to SHS exposure of 4-7 days/week.Conclusion Residents having willingness to implement smoke-free regucation might have less SHS exposure.Propaganda should be strengthened for smoke-free regulation in tobacco control.