Carcass characteristics and meat quality traits as a function of endpoint months of slaughter age (26 vs 32 mon) and chillerageing (1 vs 10 d) were evaluated for m. longissmus of 26 Hanwoo steers fed with commercial diets including whole cropbarley silage. Totally twenty six Hanwoo steers for 6 mon of age that were fed until 26 mon of age constituted the short term-fed group and fed until 32 mon of age constituted long-term fed group. Carcasses were chilled for 24 h and were graded.Strip loin samples were divided into two age groups (1 d and 10 d). Long-term feeding increased carcass weight, rib-eyearea, yield grade, marbling score, firmness and quality grade of the meat. The feeding for 32 mon produced tender, juicymeat (p<0.01) with lower cooking loss and higher rating score (p<0.05) than short term feeding, while other quality traitswere not influenced by the length of feeding. Intramuscular fat content and oxidative stability (TBARS value) were signif-icantly (p<0.05) higher in beef from long-term feeding however the length of feeding did not alter the fatty acid composi-tion. Chiller aging reduced instrumental tenderness (WBSF value), improved color, sensory tenderness, acceptability andrating of beef. The results of the present study mirrors that Hanwoo steers until 32 mon of age overall improved carcass traitsand palatability compared to that for 26 mon. However, from the viewpoints of economical and environmental aspects, costof the additional feeding for 6 mon for value-adding of eating quality was relatively high and the effects in turn were limited . Key words: Hanwoo beef, barley-based diet, meat quality, length of feeding