Analyses were conducted to estimate the effect of backfat thickness (BFT) on carcass grade factors and carcass price in Hanwoo cows and steers. Data on grade factors and prices were collected from 69,159 Hanwoo carcasses (n=13,376 cows, n=55,783 steers) abtained at the Nonghyup Seoul slaughter house in 2009. Carcass BFTs were divided into nine categories from ≤3 mm to ≥25 mm. The average BFTs were 11.93 mm in cows and 12.57 mm in steers. An increase in the BFT resulted in an increase in carcass weight, loin-eye area, skeletal maturity, fat color, but decreases in the yield index and yield grade (from grade A to C) in cows and steers. Carcass unit price (Won/kg) improved if the carcass was sold with a BFT of 13-15 mm in cows and 10-12 mm in steers. Marbling score and quality grade increased significantly to 21 mm BFT but decreased from a BFT of 22 mm in cows and steers. BFT was significantly correlated with yield index (cow, r=-0.97**; steer, r=-0.96**), marbling score (cow, r=0.20**; steer, r=0.14**), and carcass price (cow, r=0.03**; steer, r=-0.11**). These results could be used as a fundamental dataset for further research to increase the productivity of Hanwoo carcasses.