Introduction: in Colombia, economic development models have favored the exploitation of natural resources such as coal, generating health effects on population who are living inside the influence area of the production process.Objective: to determinate the relationship between symptoms related with respiratory diseases and exposure to particulate matter less than 2.5 µm (PM2.5) in students of two schools at Guachetá municipality of Cundinamarca, Colombia.Methods: a cross-sectional study was carried out in children between 4 and 17 years old, in two schools at Guachetá municipality of Colombia, where prevalence of symptoms related with respiratory diseases (dryness in the nostrils, difficulty breathing, cough and sneezing) were evaluated through an applied survey. Also, the survey asked about general data, family history, habits, perception of the environment and concern about possible health effects. Schools were located one near and the other far from open pit coal mines. For the collection of PM2.5 data was used an AirBeam device. Measurements were made during 11 days, for 6 hours per day. Descriptive statistical analysis of interest variables were performed using the SPSS software, while an analysis association between variables was carried out using the EPIINFO software.Results: daily average concentration at schools were: El Carmen (8,1 µg/m3 S.D: ± 1,61) and for Gonzalo Jiménez school (6,7 µg/m3 S.D: ± 1,9). Prevalence of symptoms related with respiratory diseases was higher for cough (74,4%) and sneezing (71%). Students from Carmen departmental school are more likely to have symptoms associated with respiratory diseases, especially difficulty breathing (OR = 5,12 p = 0,0002) that those students of Gonzalo Jiménez school. Conclusion: Children who were studying at the closest school to the open-pit coal mines had a greater presence of all symptoms related to respiratory diseases than those located at the furthest school from the mines.