Air pollution of indoor and outdoor environments is one of the most important environmental problems in metropolises and industrial cities. The study explores the effects of air quality on the well-being of students at Shahid Beheshti University in Tehran. The sampling of the particles was carried out in four seasons in 2017–2018. The concentration of PM≥11, PM7-11, PM4.7–7, PM3.3–4.7, PM2.1–3.3, PM1.1–2.1, PM0.7–1.1, PM0.4–0.7 and PM≤0.4 in inside and outside building was evaluated simultaneously using a direct measurement device. The length of each collection period varied from 6 to 72 h. The samples were studied by SEM/EDS and imaging was performed and the surface of particles. The effects of air quality on students were collected using a questionnaire. Based on the results, there was cough, throat irritation and psychological problems for students, especially those with asthma and respiratory problems. There were more symptoms during the summer and autumn. The life of the building, the use of natural ventilation and inadequate cooling devices are the main factor in increasing the concentration of indoor particles in the educational building. According to the result of sampling in the outside environment, the highest concentration of the particles occurred in summer and the lowest concentration in spring and winter. Due to the presence of natural ventilation in the spring and summer seasons, the trend of variation of the concentration inside the building was similar to the outside.
