Objective To discuss the regularity in fasting blood sugar variations following kidneytransplantation and evaluate the PTDM morbidity and the effect of fasting blood sugar on survival and complications of patients. Method 422 patients receiving kidneytransplantation in our hospital from January 2015 to December 2018 were collected. Based on the pre-operative fasting blood sugar, the patients were divided into Group DM, IFG, and NFG. The variation trends of fasting blood sugar in various groups were obtained by analysing the fasting blood sugar data of patients 3, 6, 9, 12, 24, 36, 48, and 60 months before and after operation. The PTDM occurrence conditions were analysed 3, 6, 9, 12, 36, and 60 months after operation based on the fasting blood sugar of patients; a simplified OGTT was performed for patients with their fasting blood sugar not meeting the diagnostic criteria for diabetes ≥3 years after kidneytransplantation to analyse the PTDM morbidity among patients ≥3 years after kidneytransplantation and calculate the HOMA index. The patients were divided into Group DM, IFG, and NFG based on fasting blood sugar before kidneytransplantation and PTDM Group and Non-PTDM Group. A comparison was made for the difference in survival rate among various groups. Result The fasting blood sugar in the Group DM decreased significantly compared with that before operation (P<0.05); the fasting blood sugar in the Group IFG and NFG increased compared that before operation (P<0.05). The PTDM morbidity exhibited an overall decreasing trend with time and reached as high as 52.82% 3 months after operation. HOMA-IR was the highest in Group IGR followed by Group PTDM. HOMA-IR significantly increased in Group IGR compared with the group of normal blood sugar (P<0.05). HOMA-β in Group PTDM decreased significantly compared with the group of normal blood sugar and Group IGR (P<0.05). The survival rate in Group DM significantly decreased compared with that in Group NFG (P<0.05); the survival rate in Group IFG also decreased significantly compared with that in Group NFG (P<0.05); the average survival time and survival rate in Group PTDM were significantly lower than those in groups other than Group PTDM (P<0.05). Conclusion kidneytransplantation is able to improve the fasting blood sugar of patients with diabetes and the blood sugar can significant affect the survival rate of kidneytransplantation patients and lower the survival rate of patients.