Five hundred forty four heads of Hanwoo castles (131 cows, 327 bulls, and 86 steers) were slaughtered at meat laboratory of National Livestock Research Institute, RDA, and graded at 24 hours postmortem by meat graders of Animal Products Grading Service. Carcasses were divided into 3 groups based on the lean color grades: (1) Control(486 heads) was the meat graded for standard lean color scores of No. 3, 4. or 5: (2) light dark firm dry meat (LDFD)(41 heads) was the meat graded for color scores of No. 6; (3) Severe dark firm dry meat (SDFD)(17 heads) was the meat graded for color scores of No. 7. Approximately 1.5㎏ of longissimus muscles were separated for the measurement of physico-chemical characteristics. There were no significant differences in the contents of crude protein, fat, ash, and moisture among 3 groups(p $gt; .05). SDFD were highest in water holding capacity(WHC) (67%). followed by LDFD(56.56%) and control (48.41%). Cooking loss and shear force were lowest for SDFD(26.10%. 3.04㎏/0.5 inch²) and followed by LDFD(36.71%, 5.11㎏/0.5 inch=), and control(48.41%, 5.43㎏/0.5 inch²). The highest amounts of sarcoplasmic proteins(11㎎/g) and the lowest amounts of myofibrillar proteins(6.86㎎/g) were extracted from SDFD, whereas the lowest amounts of sarcoplasmic proteins(7.53㎎/g) and the highest amounts of myofibrillar proteins(7.98㎎/g) were extracted from control. The control revealed the highest CIE values(L, a, b). Sensory evaluation showed that SDFD had the highest score for tenderness(p$lt;.05), however, there were no significant differences in juiciness and flavor (p$gt;.05). In conclusions, DFD had the higher WHC. and the lower cooking loss and shear forces when they were compared with control. Also. DFD were more tender than control.