This study analyzes the influence of fine particles PM 2.5 on nonprogrammed children's hospital admissions that occurred in the city of Seville between 2007 and 2011, and makes an economic assessment of the cost of the children's hospital admissions for respiratory causes due to particle pollution. The PM 2.5 dose-response functions for each type of hospital admission were used to quantify the cost of the hospital admissions. It can be concluded that the PM 2.5 concentrations have negative effects on bronchiolitis, pneumonia, asthma, and bronchitis and other causes. A reduction of the daily average annual PM 2.5 concentration from the existing levels to 10 µg/m 3 would show an annual average reduction of children's hospital admissions due to respiratory diseases of 0.09 cases. This paper shows that the daily average cost for children hospital admissions due to respiratory reasons in the city of Seville, associated with daily average annual levels of PM 2.5 above 10 µg/m 3 , was almost 200€.Implications: Elevated PM 2.5 concentrations in Seville have negative effects on children's bronchiolitis, pneumonia, asthma, and bronchitis and other causes. A reduction of the daily average annual PM 2.5 concentration from the existing levels to 10 μg/m 3 would suppose an annual mean reduction of children's hospital admissions due to respiratory diseases of 0.09 cases.