Objective. To estimate the mortality risk of fine (PM2.5) and coarse (PM2.5-10) particles in the Metropolitan Area of Monterrey (MAM). Materials and methods. A retrospective ecological time-series analysis (2000-2014) was conducted using total and specific causes of mortality, and daily mean PM2.5 and PM2.5-10. Generalized additive distributed lag models controlling for trend, seasonality, day of the week, meteorological conditions and gaseous pollutants. Results. Mean (SD) PM2.5 and PM2.5-10 concentrations were 26.59 µg/m3 (11.06 µg/m3) and 48.83 µg/m3 (21.15 µg/m3). An increase of 10 µg/m3 of PM2.5 (lag 0) was associated with 11.16% (95%CI:1.03-21.39) increased risk of respiratory mortality in children <=5 years old and 6.6% (95%CI 3.31-9.37) increased risk of pneumonia-influenza in adults >=65 years old. The risk of mortality associated with the concentration of coarse particles was lower. Conclusions. Positive and significant associations were observed between exposure to particulate matter and daily mortality in the MAM's population. [ABSTRACT FROM AUTHOR]