The purpose of this study is to measure agricultural waste and estimate the environmental Kuznets curve in four East Asian countries using time series data from the 1960s to the 2010s. Positive nutrient balance (NB) suggests there is pressure on arable land, causing water pollution and greenhouse gases. For crop farming, only China’s NB per arable land unit (NBAL) has risen recently, while NB per product (NBP) in all four countries has declined. Regarding livestock farming, NBAL in all countries except Japan has risen. Even more recently, China’s NBP has risen differently to other countries’ movements. The estimation results of the environmental Kuznets curve suggest China’s NBAL will rise continuously with gross domestic product per capita increases in crop farming. For livestock farming, the estimated indexes are confirmed to have worsened with the advance of economic growth.