The aim of this study was to determine the effect of gamma-oryzanol-enriched -rice bran oil on the quality of cryopreserved boar semen. Ten boars provided semen of proven motility and morphology for this study. The semen was divided into three portions in which lactose-egg yolk (LEY) extender used to resuspend the centrifuged sperm pellet was supplemented with 2 types of rice bran oils, at a gamma-oryzanol concentration of 0 mg/ml of lactose egg yolk (LEY) freezing extender (group A, control), 0.1 mg/ml(0.16 mMol) of freezing extender (group B) and 0.1 mg/ml of freezing extender (group C). Semen suspensions were loaded in medium straws (0.5 ml) and placed in a controlled-rate freezer. After cryopreservation, frozen semen samples were thawed and investigated for progressive motility, viability and acrosomal integrity. There was a significantly higher percentage of progressive motility (34 versus 47.0 and 48.5, P<0.001), viability (35.5 versus 48.1 and 50.1, P<0.001) and acrosomal integrity (39.8 versus 50.8 and 54.9, P<0.001) in the gamma-oryzanol-enriched rice bran oil-supplemented groups (groups B, C) than in the control group (group C), respectively. In conclusion, addition of gamma-oryzanol-enriched rice bran oil to LEY freezing extender is appropriated for improving the quality of frozen-thawed boar semen.