Abstract： Objective:To evaluated the antioxidant function of marine fish oligopeptide vitamin C solid beverage in healthy people.Methods:From June 1st to December 31st, 2017, 110 volunteers aged 18 to 65 years in good health were recruited by Zhejiang Provincial Center for Disease Control and Prevention, and were randomly divided into control group and test group (55 cases in each group). The test group took the marine fish oligopeptide vitamin C solid beverage (the main components were marine fish oligopeptide powder, vitamin C, acai fruit powder, blueberry fruit powder, pomegranate fruit powder), and the control group took the placebo with the same appearance, package and taste as the solid beverage (the main components were maltodextrin, acai fruit powder, blueberry fruit powder, pomegranate fruit powder). The test samples were both packaged in 5 g/bag and were taken 1 bag daily for 4 months. During the trial, both groups maintained their daily life and dietary habits, and there were no other interventions except for the test samples. During the intervention, 3 cases dropped out, and finally, 53 cases were included in the control group and 54 cases in the test group. Before and after the test, the volunteers were examined for general physical conditions, routine blood, urine and stool tests, and biochemical indicators. At the same time, the levels of blood malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured, and the differences of various indicators between the two groups before and after the test were compared by t-test. Results:There was no significant difference in baseline data between the two groups (all P>0.05). After the test, the MDA level in the test group was significantly lower than that before the test [(4.06±1.09) vs (4.73±0.99) μmol/L] ( t=15.160, P<0.001), SOD level was significantly higher than that before the test [(20 987±2 593) vs (18 564±2 194) U/gHb] ( t=-4 338.337, P<0.05), there was no significant change in GSH-Px level before and after the test ( P>0.05). There was no significant differences in the levels of MDA, SOD and GSH-Px in the control group before and after the test (all P>0.05). After trial feeding, the MDA level in the test group was significantly lower than that in the control group [(4.06±1.09) vs (4.63±0.91)] μmol/L] ( t=31.220, P<0.001), SOD level was higher than that in the control group [(20 987±2 593) vs (19 042±2 100) U/gHb] ( t=-3 124.231, P<0.05), there was no significant difference in GSH-Px level between the two groups ( P>0.05). All the test indexes in the two groups were in the normal range before and after the test; there were no abnormal changes in chest radiography, electrocardiogram and abdominal B-ultrasonography; during the trial feeding, no allergy or adverse reaction was found, and no abnormal change of subjective feeling and eating condition was found. Conclusion:Marine fish oligopeptide vitamin C solid beverage can significantly reduce the level of MDA, improve the level of SOD, it has antioxidant function and good safety.