Objective：To study the effect and safety of meal replacement assisting weight reducing camp for overweight patients after 7-day fasting.Methods：Divided 58 overweight volunteersinto weight reducing camp with 8 phases respectively.The subbjects were given meal substitute which could regulate intestinal flora without calorie.Aerobic exercise is required everyday.Observed the changes of the level of weight，blood pressure，blood glucose and body mass index(BMI)，as well as observed adverse reaction.Results：Subjects lost 5.52 kg at average within 7 days，decreasing 6.93%.The levels of blood pressure and blood glucose of all subjects were decreased significantly as well，while there was one case of reactive hypoglycemia，who was a 23-year-old woman that seldom did exercises with 25 at BMI.Conclusion：Meal replacement assisting duly fasting reduces weight safely and helps control blood pressure and blood glucose.