The purpose of this study was to measure the antioxidant activity of yacon root and to manufacture yacon pickles for commercialization as a functional food. The total phenol content in yacon roots were the highest, 29.96 mg GAE/ 100 g, in the ethyl acetate fraction and the DPPH radical scavenging activity and ABTS radical scavenging activity was 37.07%, and 91.60%, respectively, in the ethyl acetate fraction. The optimum recipe for the pickling solution was determined to be vinegar, water and high fructose corn syrup, at 34%, 22% and 44%, respectively. The quality characteristics of yacon pickles using this solution were monitored during storage at $25^{circ}C$ for 43 days. The pH value decreased to 2.98 (42 days) during storage and $^{circ}Brix$ gradually increased during storage. The L-value decreased significantly during storage but there were no significant changes detected in the a and b values. No significant changes were detected in the hardness of the yacon pickles. According to the sensory evaluation, no significant changes in taste, texture and overall acceptance of yacon pickle were observed during storage. These results indicated that yacon was an excellent functional food in terms of its antioxidant activity and that pickling might be a promising methods to maintain the taste and quality of yacon during storage.