Abstract: AIM To investigate the relationship between glucose fluctuation and macrovascular complications in type 2 diabetes mellitus (T2DM). METHODS Patients with T2DM were included in the study. The patients were divided into macrovascular complications group (66 cases) and non-macrovascular complications group (76 cases). General clinical data and laboratory indexes of the subjects were recorded. Continue glucose monitoring (CGM) was performed in both groups. RESULTS Age, duration of DM, the percentage of hyperglycemia, the area under curve (AUC) above 11.1 mmol/L, MBG, incidence of hypoglycemia, SDBG, MAGE and LAGE were higher in the macrovascular complications group than in the non-macrovascular complications group (all P<0.05 or P<0.01). There was no significant difference in the ratio of gender, smoker, hypertension, types of antidiabetic drugs, serum lipids, alanine aminotransferase, aspartate aminotransferase, FPG and HbA1c between the two groups. Stepwise logistic regression analyses indicated that macrovascular complications were positively related with age and MAGE independently. Macrovascular complications were positively related with age, duration of DM, percentage of hyperglycemia, area under curve (AUC) above 11.1 mmol/L, incidence of hypoglycemia, MBG, 2hPPG, SDBG, MAGE and LAGE using Spearman’s correlation analysis. CONCLUSION Macrovascular complications were positively related with MAGE in type 2 diabetes mellitus.