This study was carried out to compare the growth performance and quality properties of pork from finishing pigs fed different levels of betaine. A total 120 female pigs (Landrace${\times}$Yorkshire${\times}$Duroc) were fed either a control commercial diet or the control diet supplemented with 2, 4 and 6% betaine for 31 days. The average daily feed intake (ADFI) of the 2% diet was lower than of the other treatment groups. The average daily gain (ADG) for pigs fed betaine diets was significantly higher (p<0.05) compared with nonsupplemented diets. Feed conversion ratio (FCR) of pigs fed betaine diets was significantly lower (p<0.05) compared with nonsupplemented diets. pH of loin and ham samples were not significantly different between dietary groups, whereas CIE a* (redness) of pork loin was increased by dietary betaine. Also, the shear force value of loin was significantly higher (p<0.05) in pigs given dietary betaine compared with non-supplemented diets, but no significant differences were found in cooking loss by the loin among diets with different levels of betaine (p>0.05). Dietary supplementation with betaine decreased total cholesterol concentrations in blood, and increased saturated fatty acid and decreased unsaturated fatty acid levels in muscle. Pigs supplemented with betaine had increased betaine concentrations in the loin muscle. It was concluded that dietary betaine supplementation of finishing pigs can improve growth performance and reduce blood cholesterol concentrations. It was also concluded that dietary betaine produced detectable betaine concentrations in the lion muscle.