This study investigated the effects of dietary supplementation of conjugated linoleic acid (CLA) on the growth performance, carcass characteristics, muscle quality and fatty acid compositions in the skeletal muscle and backfat of growing-finishing pigs from 39.5 to 108.0 kg. Forty-eight pigs were randomly allotted to four diets containing 0 (control), 0.5, 1.0 or 1.5% of CLA mixture (35.2% cis-9, trans-11 and 37.5% trans-10, cis-12) for 12 weeks. The results showed that dietary CLA supplementation did not affect the animal’s growth performance and carcass characteristics, whereas significantly increased dry matter content of the Longissimus dorsi muscle (P<0.05). The CLA supplementation also increased the content of saturated fatty acids, but decreased (P<0.05) the content of unsaturated fatty acids (UFA) in both the backfat and Longissimus dorsi muscle. The CLA concentrations in the Longissimus dorsi muscle and backfat were increased linearly by the CLA supplementation in a dose-dependent manner. However, CLA cis-9, trans-11 and CLA trans-10, cis-12 showed different deposition efficiencies in pigs.