There are few studies showing that the increase in particulate matters less than 10 μm (PM10) values increases the apnea-hypopnea index (AHI). We aimed to investigate relationship between air quality parameters and the seasons with the AHI. This was a retrospective study that included 500 adults. Polysomnography (PSG) was performed on all patients. Oxygen saturation, air temperature, relative humidity, and PM10 values were recorded in Düzce for every year. The parameters of the national air quality network and sleep parameters of 500 individuals hospitalized between 2015 and 2017 were checked. A total of 500 patients were included in the study, of whom 316 (63.2%) were male and 184 (36.8%) were female. While the AHI value of patients who presented during 2016 was 27.5, it had significantly declined to 20.2 in 2017 ( = .024). A significant decline was observed in AHI values of OSA patients from 2016 to 2017 ( = .043). A significant positive correlation was observed between REM-related AHI and relative humidity ( = 0.183, = .002). This study showed a clear relationship between AHI and PM10 during winter when air pollution parameters are high in the region. PM10 emerged as a parameter that substantially increases the relative risk for OSA.