After HHP treatment, the hardness and color values of L*(lightness), a*(redness), and b*(yellowness) of garlic samples decreased, while the cohesiveness value of garlic samples was increased聽(P聽<聽0.05). The antioxidative, antimicrobial and antitumor activities of HHP treated garlic samples were decreased compared with control. A rapid decrease in antimicrobial and antioxidative activities was observed over 3聽min HHP reaction time. No antitumor activities were observed after 3聽min HHP reaction time. Up to 56聽s聽HHP reaction time, the alliinase activity was not changed significantly but it was dramatically decreased at a longer HHP reaction time compared with control (P聽<聽0.05), showing higher stability in acidic condition than alkaline condition. Based on present observations, this study supports high potentials of HHP treatment to produce new value-added garlic products with modified garlic flavor profile, and minimized physicochemical properties and biological activities.