This study was conducted to investigate the growth performance and economic efficiency in dietary corn mixing level on total mixed ration(TMR) in growing goats. A total of 32 castration goats with similar age (average 4 mo) and body weight (average 16kg) were equally allocated to dietary 4 treatments in a randomized complete block design. Dietary treatments included a controls (conventional) group and 3 corn mixing treatments groups (fed diets containing 15, 25, 35% corn mixing level of TMR). Average daily gain (ADG) was significantly (P < 0.05) higher in control group (103.5g). Within treatments, ranked the highest in 25% (91.2g), 15% (84.8g) 35% (72.6g) corn mixing treatments (P < 0.05). Daily feed intakes was significantly (P < 0.05) higher in control group (1,076g). Within treatments, ranked the highest in 15% (1,050g), 25% (1,041g), 35% (1,015g) corn mixing treatments (P < 0.05). The amounts of feed required for body weight gain ranked the lowest in control group (10.4), followed by 15% (11.4), 25% (12.4) and 35% (14.0) corn mixing treatments (P < 0.05). However, comparing the feed cost contrast with market price for economic analysis by comparing the income results, the income ranked the highest 396Won (36cents) in 25% corn mixing treatments, followed by 15% corn mixing treatments 344Won (31.2cents), control group 322Won (29.2cents) and 35% corn mixing treatments 254Won (23cents)(P < 0.05). In conclusion, it was estimated that the optimal level of corn mix on TMR might be 25% feed intake, when diets based TMR were fed to growing Korean black goats for their improvements of economic efficiency.