The applicability of electronic nose was tested to detect lipid peroxidation in chickens and to measure antioxidant effect of astaxanthin in chicken carcasses. Two sources of astaxanthin were fed to 62-wk-old spent laying hens to improve meat quality: natural astaxanthin (NA) from the red yeast, Phaffia rhodozyma, and synthetic astaxanthin (SA) from chemical synthesis. One hundred forty four ISA Brown laying hens were used in a 6-wk feeding trial. Three treatments consisted of the basal diet (control), SA (100 mg astaxanthin/kg basal diet) and NA (50 mg astaxanthin/kg basal diet). The astaxanthin levels of SA and NA were set to give a similar degree of skin pigmentation. After 6-wk feeding of astaxanthin, the skins from NA and SA were discriminated from the control by electronic nose. However, electronic nose failed to distinguish between SA and NA skins after 6-wk feeding. The astaxanthin level differences between skins of SA and NA were not remarkable during the 6-wk trial. The lipid peroxide formation in skin was significantly decreased by SA but not by NA. The antioxidation effect of SA was detected by electronic nose because SA skin was discriminated from others. NA was a better pigmentation agent than SA, but the reverse was true in antioxidation. Electronic nose is applicable for detecting astaxanthin in chicken, and meat off-flavor caused by lipid peroxidation during storage.