This study suggested a framework for analyzing the ex post impacts of agricultural market-opening on social welfare and agriculture-related industry. In this study, 19 major agricultural products were considered, which hold about 64% of total agricultural production. The ex porst impacts of market-opening were defined as the net import changes estimated by subtracting the trend forecast from realized import. We also estimated the impacts on the agriculture-related industry by employing an Input-Output model with 404 sectors. This study estimated not only negative effects of agricultural production losses but also positive effects of real income growth due to price decrease. The findings are as follows. While consumer surplus gain (611 billion Won per eyar) is higher than farmer surplus loss (563 billion Won per year), farmer surplus loss per household is much higher than consumer surplus gain per household. Total impacts of agricultural market-opening including inter-industry effects was estimated as much as 830 billion Won per year. The distribution of inter-industrial impacts are quite different across industries, ⅰ.e. the input industry of agricultural sector suffered from agricultural prodcution decreases, while the food manufacturing the service industry benefited from income effects due to price decline.