Objective To investigate the efficacy of dualchannal anastomosis of residual stomach and jejunum after proximal gastrectomy in nonobese type 2 diabetes mellitus patients.Methods Retrospectively analyzed the clinical data of 55 patients of proximal stomach cancer complicated with type 2 diabetes mellitus （BMI＜27.5 kg/m2）who were admitted into our hospital from June 2015 to September 2016. Among them

25 patients received dualchannel anastomosis of gastric jejunum after proximal gastrectomy (dualchannel group)

and the other 30 patients received Roux-en-Y jejunostomy after total gastrectomy (R-Y group).The changes of blood glucose before and after operation and the nutritional indexes after operation were analyzed.Results The levels of fasting blood glucose

postprandial blood glucose and glycosylated hemoglobin in the two groups were significantly lower than those before the operation

and the differences were statistically significant (P<0.05).There was no statistically significant difference in blood glucose improvement between the two groups (P>0.05).Twelve months after surgery

the complete response rate in the dualchannel group was 68%

and it was 66% in the R-Y group

and there was no significant difference between the two groups (χ2=2.843，P>0.05).Nutritional indexes such as BMI

hemoglobin and plasma albumin in the dualchannel group were significantly better than those in the R-Y group

and the difference between the two groups was statistically significant (P＜0.05). Conclusion Both dualchannel anastomosis after proximal gastrectomy and RouxenY jejunostomy after total gastrectomy can receive good effect for the treatment of nonobese T2DM patients

but the former has more advantages in terms of postoperative nutritional status.