To determine the concentration of particulate matters (PM2.5 and PM10), 36 samples were collected from indoor/outdoor air of hookah cafes (HS), cigarette cafes (CS), both hookah and cigarette (HCS), and no-smoking building (NS) in Tehran City from December 2017 to March 2018. The mean ± SD of PM10 concentration in the indoor air of the cafes in terms of HS, CS, HCS, and NS sites has been 702.35, 220.20, 1156.60, and 60.12 μg/m3, while for PM2.5, the values have been 271.92, 111.80, 619.10, and 22.25 μg/m3, respectively. It was also found that the PM concentration inside the cafes was higher during weekend session (with a higher number of active smokers), than during the weekday sessions. Moreover, the PM levels in the indoor air of the cafes were considerably higher than those of the outdoors (p