Ganoderma lucidum has been reported to have various biological activities including antioxidant activity. The objective of this study was to compare the antioxidant effects between Ganoderma lucidum (GL) and antler-shaped fruiting body of Ganoderma lucidum (AGL). In vitro antioxidant activities were examined by 2,2-diphenyl-picrylhydrazyl hydrate (DPPH) and 1,2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities of GL and AGL ethanol extracts. In the DPPH and ABTS radical scavenging activities of GL and AGL ethanol extracts, antioxidant activities of AGL extracts (IC50, 66.94 μg/ml and 131.23 μg/ml) was showed higher than GL extracts (IC50, 83.93 μg/ml and 164.54 μg/ml). Total polyphenol content and total flavonoid content (38.00 g GAE/kg extract and 11.58 g NE/kg extract) of AGL were found higher as compared to GL (34.23 g GAE/kg extract and 3.46 g NE/kg extract). In summary, the results of this study demonstrate that AGL extracts had higher antioxidant activities to GL.