Air pollution has become one of the world's biggest concerns, as it is increasingly causing harmful effects on people's health. One of the biggest air pollutants causing these effects is particulate matter, exposure to which is associated with various respiratory and cardiovascular health problems. The aim of this study was to assess the indoor air quality in the bedrooms of university students living in Coimbra, as well as the effects on their health. Data collection consisted of two stages of investigation, the first being an assessment of the air quality in the target population's homes. The second stage consisted of administering a questionnaire to the students who took part in the study. It was found that indoor air quality has an influence on students’ health, particularly on sleep quality and chronic respiratory or cardiovascular diseases, even if they don't realize it. The variables under study, namely PM2,5, PM10, CO and CO2, Temperature and Relative Humidity, did not exceed the protective threshold values and the legally established ranges, however, statistically significant differences were revealed in certain parameters. Intervention is needed regarding measures concerning particulate matter so that it does less and less harm to the health of the general population.