This study was conducted to determine the effects of total mixed fermentation (TMF) with bean curd dregs on body weight gain, feed intake and body size of growing Hanwoo heifers. Thirty Hanwoo heifers, 6 months of age and weighing $125.9{pm}12.0$ kg, were randomly allocated to 3 experimental groups of 10 animals each for a 6-month feeding trial. The groups were T1 (rice straw offered ad libitum with restricted (1.7% BW/day) concentrate), T2 (TMF only offered ad libitum) and T3 (TMF and rice straw offered ad libitum with restricted (1.0% BW/day) concentrate). TMF feeds were composed of 60% bean curd dregs, 16.5% corn meal, 10.4% wheat bran, 5% rice straw, 7% rice hulls, 0.5% urea matter, 0.5% magnesia lime and 0.1% lactic acid bacteria. The chemical composition and pH value of TMF feeds were measured at 0, 24, 48 and 72 hr after storage. In TMF with bean curd dregs, there were no differences in concentrations of DM, EE, and CF according to storage periouds. The ADF and NDF at 72 hr of storage time showed a significant decrease (9.52 and 3.15 %, respectively) compared to 0h of storage time (p<0.05). The value of pH was gradually decreased during the storage periods. Body weight gain, feed intake and average daily gain were higher in the TMF groups (T2, T3) compared to the T1 group (p<0.05). Changes in body size were also higher in the TMF groups compared to the T1 group (p<0.05). Thus, the present results indicate that TMF with bean curd dregs may help improve growth performance in growing Hanwoo heifers.