Objective To understand the awareness of the health co-benefits of carbon emission reduction in urban residents in Beijing and the influencing factors, and provide information for policy decision on carbon emission reduction and health education campaigns. Methods Four communities were selected randomly from Fangshan, Haidian, Huairou and Dongcheng districts of Beijing, respectively. The sample size was estimated by using Kish-Leslie formula for descriptive analysis. 90 participants were recruited from each community. chi~2 test was conducted to examine the associations between socio-demographic variables and individuals awareness of the health co-benefits of carbon emission reduction. Ordinal logistic regression analysis was performed to investigate the factors influencing the awareness about the health co-benefits. Results In 369 participants surveyed, 12.7% reported they knew the health co-benefits of carbon emission reduction. The final logistic regression analysis revealed that age (OR=0.98), attitude to climate warming (OR= 0.72) and air pollution (OR= 1.59), family monthly average income (OR= 1.27), and low carbon lifestyle (OR= 2.36) were important factors influencing their awareness of the health co-benefits of carbon emission reduction. Conclusion The awareness of the health co-benefits of carbon emissions reduction were influenced by people' socio-demographic characteristics (age and family income), concerns about air pollution and climate warming, and low carbon lifestyle. It is necessary to take these factors into consideration in future development and implementation of carbon emission reduction policies and related health education campaigns.