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Background and Objective: Zinc and Copper are the important trace elements for human growth and body’s biological functions. These trace elements are the important cofactors of many enzymes. Serum variation of these trace elements are clinically important and should be taken into consideration, because fluctuation of these elements are behind many clinical manifestation in human. Diarrhea and vomiting can be the clinical symptoms associated with the toxic level of Zinc and Copper in the body. The concept behind this study is to determine the serum levels of Zinc and Copper in hemodialysis patients before and after dialysis, to explain the differences of such trace element concentration in these patients. Materials and Methods: This project is a comparative study. The sample population was 50 of hemodialysis patients chosen randomly from the patients referred to the 5th Azar Hospital in Gorgan (33 male and 17 female). The concentration of Zinc and Copper of these patients was determined before and after the dialysis. Results: The results from this research projects indicated that the average concentration of Zinc and Copper in hemodialysis patients after dialysis were 135.32±59.32 and 136.40±51.52 microgram/deciliter which markedly increase in compare to the serum concentration of these trace elements before the dialysis which were 78.38±37.46 and 89.92±32.54 microgram/deciliter respectively. On the basis of the results, we found in this study the average increased concentration of Zinc and Copper after the process of dialysis among the hemodialysis patients had a meaningful statistical variation (P<0.001). Conclusion: Uremia, dialysis blood tube, heavy metal contamination, the quality of dialysis membrane and the quality of water used for the process of dialysis can be a reason for the increased concentration of Zinc and Copper. Such increase in the serum concentration of these trace elements can be the basis for some clinical abnormalities. Therefore it is suggested to determine the rate of released Zinc and Copper from hemodialysis machine, before the procedure is done To enable the medical team to evaluate the serum Zinc and Copper and correct it by nutritional therapy.