Fluctuations in atmospheric temperature, humidity, and air pollution are associated with the incidence of epistaxis. To date, no study in the literature has evaluated the effect of air pollution and meteorologic conditions on the pediatric population. We aimed to evaluate the effect of meteorologic factors and air pollution on the frequency of epistaxis in children. Children presenting to an outpatient clinical setting at a tertiary care hospital during a 5-year period (July 1, 2009, to June 30, 2014) and diagnosed with epistaxis formed the study population. Daily temperature and humidity parameters and average daily atmospheric water vapor pressure, average daily concentration of particulate matter <10 μm in diameter, and sulfur dioxide readings were obtained. The distribution of daily parameters was analyzed. Of the 1,559 children with the primary diagnosis of epistaxis, data from 1,330 children were analyzed after excluding patients with coexisting pathologies. Positive correlations were found between the frequency of epistaxis and both the average daily temperature and the difference between the maximum and minimum daily temperature. There was a negative correlation between the epistaxis frequency and the average daily humidity, the difference between the maximum and minimum daily humidity, the average daily concentration of particulate matter, and the sulfur dioxide levels. Our findings suggest that epistaxis in children is related to high temperatures and low humidity.