The objective of this study was to examine the quality characteristics and antioxidant activity of yogurt containing hot water extract from maca. Four different levels (0, 4, 8, 12%) of maca extract were added to milk followed by fermentation with lactic acid bacteria at $37^{circ}C$ for 12 hrs, and then the physicochemical properties of the samples were investigated. During 7 days of storage at $4{pm}1^{circ}C$, the acid production (pH and titratable acidity) of the yogurt increased with the addition of maca extract. The Hunter L value (lightness) decreased, while the b value (yellowness) increased as the maca extract level in the yogurt increased. Viable cell counts were not significantly different among the samples. The results of consumer acceptance tests showed that no significant differences in overall acceptability were observed between the yogurts containing 4% and 8% of maca extract and a control yogurt. The yogurt containing maca extract exhibited higher DPPH radical and superoxide anion radical scavenging activities than the control yogurt over the storage period.