The annual air pollution emissions from construction and agricultural equipments were estimated from 1987 through 2000. The annual numbers and operation hours of 5 major construction equipments (Excavator, Bulldozer, Loader, Fork lift, Crane) and 3 major agricultural equipments (Power Tiller, Agricultural Tractor, Combine) were investigated for emission estimation. And monthly variation factors of operation hours of construction equipment were investigated too. The NO$_{x}$ emission from construction equipment have been gradually increased since 1987 to 1997, but sharply decreased as -45％ in 1998 due to economic crisis in Korea. The NO$_{x}$ emission was estimated as 64,300 ton/year from construction equipment, and as 23,300 ton/year from agricultural equipment in 2000.000.