The objective of this study was to investigate effects of supplementation levels of L-leucine in low-lysine diets on growth performance and meat quality parameters in finishing Duroc pigs. A total of fifty-four pigs with an average initial weight of 74±1kg were allotted to one of three dietary treatments. Each treatment had six replications of three pigs per replicate. The treatment diets included 1)a corn-soybean meal basal diet containing lysine as low as 0.45% (CON), 2) basal diet plus 1.5% L-leucine (LEU 1.5), and 3) basal diet plus 3.0% L-leucine (LEU 3.0). No difference was found in ADG, ADFI and Feed/Gain among treatments. In carcass parameters, dressing precent and back-fat thickness were not affected by L-leucine levels, however, longissimus dorsi area tended to increase by supplementation of L-leucine. Marbling score was significantly higher (P<0.05) in LEU 1.5 and LEU 3.0 than in CON. In meat quality parameters, CIE L* of meat color significantly increased (P<0.05) and crude fat tended to increase by supplementation of L-leucine. However, there was no difference in water holding capacity, cooking loss and shear force value. This study suggests that dietary supplementation of L-leucine in low-lysine diets at the end of finishing period can produce high marbled pork which is preferred by Korean consumers.