Background: Water-pipe smokers are exposed to several toxicants, including carbon monoxide (CO), causing potential health effects. Objectives: The aim of the study was to investigate demographic features and exhaled CO levels of water pipe smoking (WPS) young. Methods: The study was implemented at the outdoor areas of WPS cafes, in Ankara, in August. Demographic characteristics and exhaled CO levels of young were detected before and after one hour of WPS. Findings:. Mean exhaled CO levels before and after WPS were 1.4±1.2 ppm (min 0.1-max 5.6) and 9.4±5.3 ppm (min 3-max 25), respectively (p=0.001). Males and cigarette smokers had higher mean exhaled CO levels, before WPS (p=0.033 and p=0.001, respectively). A significant correlation was detected between duration of WPS and with exhaled CO levels before (p=0.005, r=0.363) and after WPS (p=0.039, r=0.270). In association with the rise in daily number of cigarettes, a rise in exhaled CO levels was detected after WPS (p=0.044, r=0.383). Conclusions: In Ankara, nearly half of WPS young are also cigarette smokers, are mostly students or unemployed, and WPS is perceived as a social event. Mean post-WPS levels were lower compared to previous studies, because study was conducted in the open and non-polluted air. Males, cigarette smokers and longer years of WPS practice are associated with higher mean exhaled CO levels, suggesting that these groups are subject to more health detriment risks caused by CO exposure. Large cohort studies, especially targeting high-risk groups are needed in understanding how to curb WPS and take environmental and policy controls.