Objective To study the relationship between interdialytic weight gain (IDWG%) and patients survival. Methods A retrospective study was performed with 144 stable hemodialysis patients treated in our center during 1995 and 2003. Patients were divided into two groups, group A (IDWG%≤6％) and group B (IDWG%＞6％). Life table and Cox's proportional hazard model were used to determine the hazard fac tors. Results For the entire study cohort, the mean IDWG% was 5 .83％. Five-year survival rate was poorer in group A (31.9％ vs. 57.3%, P=0.002). IDWG% was enrolled in Cox model even after adjusting the effects of patient's age, gender and serum albumin level. The relative risk was 1.34 (P=0.003). Conclusions IDWG% is a hazard factor to hemodialysis patients, a greater IDWG% is associated with a better prognosis. This relationship is valid even after the adjustment of patient's age, gender and serum albumin level.