This study investigated the effect of different levels of dietary supplementation with alpha-tocopherol or Se, or both, on growth performance and meat quality of broiler chickens. A total of 270 broiler chickens were assigned to 6 dietary treatments (0, 50, 100, or 200 IU of supplemental alpha-tocopherol; 0.3 ppm supplemental Se; or 100 IU of alpha-tocopherol plus 0.3 ppm Se) with 3 replicates of 15 chickens per pen. Growth performance was recorded at 1 and 35 d. At the end of this experiment, 10 broilers per pen were slaughtered, and thigh muscle was dissected from each carcass and stored at 4 degrees C for 1, 3, 7, and 10 d. During the experimental period, none of the experimental treatments significantly influenced the growth performance of broilers. Thigh muscle pH values of all treatments decreased over time. The pH values for 1, 3, and 10 d were not affected by all treatments, but a statistical difference among treatments was observed at 7 d. Thiobarbituric acid reactive substances and total plate counts in all treatments increased with increasing storage time. In TBA reactive substances values, there were significant differences (P < 0.05) among treatments during the storage period. Differences among treatments in total plate count were found at d 7 and 10. In all treatments, L* (lightness) and b* (yellowness) values decreased over time, and a* (redness) values increased with storage time. Significant differences in all treatments were found for L* values at 3 d and a* values at 7 and 10 d of storage. Overall, these data indicate that compared with other treatments, supplementation with 200 IU of alpha-tocopherol or 100 IU of alpha-tocopherol plus 0.3 ppm Se were most effective in increasing lipid oxidative stability and delaying microbial growth and these activities were not associated with pH.