Abstract: Objective To observe the effect of parsweet sugar and its key component,erythritol,on glucose metabolism in Kunming and Kkay mice with diabetes mellitus（DM）. Methods Kunming and Kkay mice with DM were randomly divided into experiment group and control group according to their fasting blood glucose（15 in each group）.Mice in experiment group were given 2mg/g erythritol and 2mg/g glucose,or 2mg/g erythritol and 2mg/g starch,while those in control group were given only 2mg/g glucose or only 2mg/g starch.Blood glucose level and area under blood glucose curve at different time points were compared.Postprandial insulin levels were measured in mice after 2mg/g parsweet sugar and 2mg/g starch or 2mg/g erythritol and 2mg/g starch were given,while those in control group were given only 2mg/g starch.Blood insulin level 1h after gavage was detected. Results The blood glucose levels were significantly lower in normal and DM mice than in controls 30 minutes after erythritol and glucose were given,or 30 minutes after erythritol was given and 1 hour after starch was given.The area under blood glucose curve was significantly lower in normal and DM mice after erythritol was given than after starch was given.No significant difference in blood insulin level was found in Kunming and Kkay mice 1 hour after parsweet sugar,erythritol and starch were given. Conclusion Parsweet sugar and its key component,erythritol,can decrease the postprandial blood glucose and insulin levels and even the area under blood glucose curve after meal.