A Linear Approximated Inverse Alomst Ideal Demand System suggested by Eales and Unevehr was estimated using monthly data of beef carcass grades in Korea. LA/IAIDS consists of 5 demand equations of Korean beef carcass for Hanwoo 1+ and over, 1, 2, 3 grades and Beef Cattle. The results showed that price flexibility and scale flexibility are both negative, as we expected. The responses of Korean beef price to 1% increase in imported beef quantity were 0.04~0.2% decline in low-grade beefs while 0.02~0.08% increase in Hanwoo high-grade beef. We also found that both own-price flexibility and scale flexibility of high-grade beef are much greater than those of low-grade beef. This implies that Hanwoo cattle farmer might be in the face of deficit operation due to long-terms fattening with high-grade beef price plummeted, if the numberof Hanwoo cattle continues to increase much faster than before.