This study was performed to evaluate the changes of carcass traits and early prediction of meat yieldof Hanwoo steers using ultrasound. Seventy five Hanwoo steers were ultrasonically scanned at 12, 15, 18,21 and 24 months of age for meat productivity evaluation. To make early prediction of carcass yield grade,ultrasound measure for one hundred fifty seven Hanwoo steers was done at 18, 21 and 24 months of age.Ultrasonic yield grade at 18, 21 and 24 months of age were predicted by regression method. Classifyingby carcass yield grade, ultrasonic back fat thickness at 18, 21 and 24 months of age was significantlydifferent in each carcass yield grade (p<0.05). The prediction accuracy of carcass yield grade by regressionmethod was 80.2% at 18 months, 80.3% at 21 months and 87.2% at 24 months of age. From these results,ultrasound measurement might be a useful technique to predict the carcass trait and meat yield grade inHanwoo steer.