This study was performed to examine the effect of particulate matter less than 10 ${mu}m$ in diameter($PM_{10}$) on respiratory-related admission in Seoul, 1999. Daily counts of respiratory-related admission were analyzed by generalized additive model with adjustment for effects of air temperature, humidity, and day of the week as confounders in a nonparametric approach. The results follow associations between $PM_{10}$ and asthma, acute upper respiratory disease, acute lower respiratory disease, pneumonia, and chronic respiratory disease. The relative risks were 1.30(95% CI=1.14$sim$1.50) for pneumonia, 1.18(95% CI=1.01$sim$1.37) for acute lower respiratory disease in less than 15 years, respectively. The relative risks were 1.85(95% CI=1.22$sim$2.81) for acute lower respiratory disease, 1.28(95% CI=1.04$sim$1.57) for asthma, 1.25(95% CI=1.01$sim$1.54) for pneumonia and 1.19(95% CI=1.01$sim$1.41) for acute upper respiratory disease in 15 to 64 years, respectively The relative risks were 1.54(95% CI=1.15$sim$2.08) for asthma, 1.38(95% CI=1.06$sim$l.80) for chronic respiratory disease in more than 65 years, respectively. The study showed that $PM_{10}$ was considerably affects daily counts of respiratory-related admission in Seoul, 1999 Statistically significant associations were mostly found in the adult group like If to 64 years. The highly relative risks come out in the elderly.