Wild-garlic (Allium victorialis L.) is a perennial plant found in worldwide and has been considered as a favorite vegetable due to its particular smell and taste. However, the study of biological activity of wild-garlic and the development of processed food are in rudimentary. In this study, we evaluated several biological activities, including antioxidant, antimicrobial, and inhibitory activities against human thrombin, $alpha$-amylase and $alpha$-glucosidase, of Ulrung wild-garlic. Analysis of the composition showed that Ulrung wild-garlic is nutritive although it is perishable. The color of fresh juice was stably maintained during 10 days-storage at $4^{circ}C$, but rapidly discolored by heat treatment at $70^{circ}C$ for 1 h. During heat treatment, the contents of total sugar and total polyphenol were decreased to 75% and 50%, respectively, and acidity was increased from 0.069% to 0.111%. In a while, the brix, reducing sugar, and total flavonoids showed minor changes. The fresh juice showed strong DPPH scavenging activity, reducing power and antibacterial and antifungal activity, but the heat-treated juice lost the antioxidant and antimicrobial activities. The inhibitory activities against human thrombin and $alpha$-amylase and $alpha$-glucosidase was negligible in both fresh juice and heat-treated juice. These results suggested that the antioxidant and antimicrobial components in wild-garlic are heat-liable and volatile. Based on our results, we propose non-heat treatment products for processed wild-garlic, for example, fresh juice-added beverage or fermented liquors using wild-garlic.