In this research, the effects of aging on some of the textural quality characteristics of Longissimus dorsi (LD) and Semimembranosus (SM) muscles from mutton carcasses were evaluated. The results showed that the aging process significantly (P<0.01) improved panel tenderness, number of chews and fragmentation index values. Also, the aging period significantly (P<0.05) affected some Instron parameters. While the muscle type did not significantly influence these parameters, the hardness and chewiness values measured by the Instron were significantly (P<0.01) affected by muscle type, and the values were 4.84, 6.06 kg and 1.78, 2.40 kg For LD and SM muscles respectively. in conclusion, the application of the aging process for mutton carcasses from ewes could be beneficial for the meat industry by increasing the merchandising quality of this kind of carcasses.