Abstract: Objective：To observe the changes of metabolic parameters and islet function, and to explore the relationships between liver fat content (LFC) and islet function in inpatients of type 2 diabetes mellitus patients with different duration. Methods：Totally 214 diabetic patients and 65 non-diabetes patients from January 2016 to March 2017 were collected. LFC was determined by proton magnetic resonance spectrum analysis (1H-MRS), the first-phase insulin secretion was estimated by arginine test, and insulin secretion index (HOMA-β) and insulin resistance index (HOMA-IR) were assesses by homeostasis model assessment. The changes of the parameters and their relationships were analyzed in each group. Results：Along with the course of disease, the first-phase insulin secretion, HOMA-β and LFC decreased gradually, some parameters such as serum creatinine (SCr), high density lipoprotein cholesterol (HDL-c) and microalbuminuria increased gradually, while there was no significant change in HOMA-IR. Correlation analysis demonstrated that the beta cell function (including the first-phase insulin secretion and HOMA-β) was positively associated with LFC, body mass index (BMI), body weight, waist circumference, hip circumference, serum uric acid (UA), aspartate aminotransferase (AST),triglyceride (TG),waist-hip ratio (WHR, only HOMA-β), alanine aminotransferase (ALT, only the first-phase insulin secretion) and glutamyl transferase (GGT, only the first-phase insulin secretion), all P<0.05, and was negatively associated with glycosylated hemoglobin (HbA1c), the course (only the first-phase insulin secretion), HDL-c (only the first-phase insulin secretion), all P<0.01. There were no correlations between beta cell function and the other factors including gender, age, urea nitrogen (BUN), SCr, total cholesterol (TC), low density lipoprotein cholesterol (LDL-c). Stepwise regression analysis showed that there was independently positive correlation between the first-phase insulin secretion and BMI. There were independently positive correlations between HOMA-β and HOMA-IR and BMI in diabetic patients. Conclusions：Along with the course of disease, the degree of insulin resistance is not significantly changed,while the beta cell function and LFC decreased gradually.