This study was evaluated to know the effects of vitamin E(VE) on the lipid peroxidation in blood and sirloin of castrated korean indigenous beef cattle. Experimental groups were divided into VE 500IU(A), 1,500IU additative feeding group(B) and non-VE-treated control group(C). After oral administration to the cattle for 120 and 150 days, body weight gains, VE contents in plasma and sirloin, and thiobarbituric acid(TBA) value were examined according to the exhibition period(1-7 days) in refrigerated showcase between aging and non-aging group. The results obtained from this study were summarized as follows ; 1. Body weight gain per day of control compared with VE additative feeding A and B groups were showed no significantly differences. 2. The concentrations of VE in plasma after oral administration with VE for 120 days were significantly increased(p<0.05) in A and B groups. There were higher(p<0.n) 4.22$mu extrm{g}$/$mell$ in A and 6.22$mu extrm{g}$/$mell$ in B group than the control(3.0$mu extrm{g}$/$mell$). And the concentrations of VE in plasma for 150 days were significantly increased(p<0.05) in VE additative feeding groups. There were higher 4.89$mu$g/$mell$ in A and 7.05$mu extrm{g}$/$mell$ in B group than the control(3.15$mu extrm{g}$/$mell$). 3. The concentrations of VE in sirloin for 120 days were significantly increased(p<0.05) in A and B groups. There were higher 1.84$mu extrm{g}$/g in A group and 2.40$mu extrm{g}$/g in B group than the control(0.78$mu extrm{g}$/g). And the concentrations of VE in sirloin for 150 days were significantly increased(P<0.05) in A and B groups. There were higher 1.94$mu extrm{g}$/g in A group and 2.63$mu extrm{g}$/g in B group than the control(1.00$mu extrm{g}$/g). 4. TBA values, the indicator of lipid peroxidation, in non-aging sirloin according to the exhibition period(1-7 days) in refrigerated showcase after oral administration with VE additative feed for 120 days were lower 0.73 in A and B groups than 0.82 in control at the third day after exhibition. In the same group, TBA values were significantly(p<().05) tower 0.77 and 0.75 in A and B groups than 1.22 in control at the seventh day after exhibition. Equally, in the aging group, there were significantly(p<0.05) showed lower TBA values 1.05 and 0.99 in A and B groups than 1.87 in control at the seventh day after exhibition. 5. After oral administration with VE additative feed to the cattle for 150 days, TBA values in non-aging sirloin according to the exhibition period(1-7 days) in refrigerated showcase were significantly(p<0.05) decreased to 0.84 and 0.88 in A and B groups than 1.26 in control at the seventh day after exhibition. In the aging group, there were significantly(p<0.05) showed lower TBA values 0.95 and 0.99 in A and B groups than 1.79 in control at the seventh day after exhibition.