Mung bean seeds were soaked in 0.5 g/L of sucrose solution for 24 hr at 25°C and sprayed with this solution every 12 hr during the germination for 5 days. Our results showed that exogenous sucrose significantly increased vitamin C content throughout germination, and sucrose‐treated sprouts had 23% more vitamin C (20.8 mg/100 g FW) than in control sprouts on day 5. This may be related to higher levels of glucose and l ‐galactono‐1, 4‐lactone dehydrogenase activity seen in the treated group versus the control. Total phenolic content and activities of superoxide dismutase, catalase, and ascorbate peroxidase were significantly higher in sucrose‐treated mung bean sprouts than the controls, which contributed to the higher antioxidant activity in sucrose‐treated sprouts. These results indicate that exogenous sucrose treatment increases the content of vitamin C and total phenolics, and enhances the antioxidant activity in mung bean sprouts. It suggests that exogenous sucrose treatment could be an effective technique for producing mung bean sprouts with more vitamin C and higher antioxidant capacity.