Abstract: Objective To analyze the causes of death in ESRD patients undergoing HD who died within the first 3 months of hemodialysis, and to explore the risk factors affecting survival, thus to provide some potential ways to improve the survival of HD patients, especially for the survival within the first 3 months. Methods All patients with ESRD starting hemodialysis between January 1,2010 to December 31, 2013 in Department of Nephrology, West China Hospital were included and followed-up until March 1, 2017. Baseline characteristics and laboratory results of patient who died within the first 3 months and patients who survived the first 3 months were analyzed. Logistic regression was used to analysis the risk factors associated with death within the first 3 months. Results Four hundred and thirty-eight cases in total 1268 HD patients died in the study period, among which 155 patients died within the first 3 months after the beginning of hemodialysis, characterized as the peak of death occurred within the first 3 months, accounting for 35.4% of all died HD patients. The top three primary causes for renal diseases were as follows:chronic glomerulonephritis (50.47%), diabetes (23.03%) and hypertension (9.31%). For those patients who died within the first 3 months, the top three primary causes of renal diseases were as follows:diabetes (32.3%), chronic glomerulonephritis (23.2%), hypertension (15.4%). Logistic regression analysis showed that increased Charlson comorbidity index (CCI), diabetes as primary cause of renal diseases, increased neutrophil ratio, red blood cell distribution width, continuous renal replacement therapy (CRRT)were risk factors of death within the first 3 months, whereas serum albumin, high-density lipoprotein cholesterol were protective factors. The number of patients whose primary causes of renal disease were diabetes were 292. Fifty patients died within the first 3 months, and 242 patients survived longer. CCI, CRRT, higher neutrophil ratio were risk factors for patients whose primary causes of renal disease were diabetes. Compared with the patient with chronic glomerulonephritis, the common risk factor was CRRT. The unique risk factor of patient with chronic characterized was red blood cell distribution width and the unique protection factor is higher HDL. Conclusions The risk of death within the first 3 months of hemodialysis is high. Active treatment of patients' complications and low protein status may help to improve the early survival rate of patients. Diabetes is one of the common primary causes and death risk factors in ESRD patients, which deserves attention.