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Introduction: End stage renal disease (ESRD) is a major health problem and each year the number of patients is increasing. If the disease becomes irreversible, patients must always be hemodialyzed. Since mortality rate will increase due to inadequate dialysis, determining the efficacy of hemodialysis and improving its quality is very important. The main goal of this research is investigating the efficiency of hemodialysis. Materials and Methods: This is a cross-sectional analytical study which was conducted on 103 people who were under dialysis treatment in the Vali-e-Asr hospital of Arak in year 2003. Weight, blood pressure (before and after dialyze), time of dialysis, BUN and Cr before dialysis and 5 minutes after turning of the pump and before the second dialysis were measured. Data was analyzed by T test and Pearson correlation. Results: The mean of KT/V was 0.58 ± 0.1 normal protein catabolic rate (nPCR), 0.36 ± 0.11 g/kg per day and time average concentration of urea (TAC), 43.3 ± 14 mg/d which had a significant difference with standard measures (p<0.05). KT/V was 0.49 ± 0.18 and 0.47 ± 0.10 for men and women respectively which was significantly different (p<0.03). There was a positive and linear relationship between education level and TAC, KT/V and number of dialysis per week. Conclusion: Regarding the low efficiency of hemodialysis in 80% of patients and lower levels of hemodialysis efficacy indicators in comparison to standard measures, periodic assessment and also investigating the reasons of low efficacy of hemodialysis is recommended.