This study was conducted to examine the effect of fermented alcoholic feedstuff(FAF), sustained-releaserecombinant bovine somatotropin(rBST) on growth performance and body size of Korean native cattle, Hanwoo.The experiment was carried at the Livestock Breeding Station in Kangwon-do with fourteen bulls of two groups,control and treatment. Seven bulls per each group were allocateed. In control group, bulls were treated withtotal mixed ration(TMR) for the whole experimental periods. In treatment group, bulls were treated withTMR+FAF+rBST for the fattening period and TMR+FAF for the finishing period, respectively. The results aresummarized as follows ; Average daily gains(ADG) of control and treatment groups were 0.86 and 1.11kg duringthe fattening period. ADG of treatment group were 29.1% higher than that of control group. For the wholeexperimental period, the fattening period and finishing period, ADG in control and treatment groups were 0.69and 0.79kg, respectively, which shows 14.5% improvement of ADG in treatment group. Dry matter intake(DMI)was higher in treatment group than in control group during the finishing, fattening or whole experimental period.Feed conversion efficiencies in fattening period were 8.65 for control group and 6.93 for treatment group whichshows improving 19.9% of feed conversion efficiency for treatment group, while 12.38 for control group and14.48 for treatment group in finishing period. There were no significant differences between control and treatmentgroup in feed conversion efficiency for the whole experimental period. Overall results indicate that the favorablefeeding system to produce growth performance is TMR+FAF+rBST feeding during the fattening period andTMR+FAF feeding in treatment during the finishing period.