In patients with end-stage renal disease, depressed taste acuity may often affect their food intake and causes malnutrition. We measured mean recognition thresholds for the four primary tastes before and after hemodialysis to evaluate the efficacy of hemodialysis on taste acuity and measured serum zinc concentrations to determine the relationship between taste acuity and zinc status in 21 patients undergoing hemodialysis. The results were as follows : 1) Mean taste recognition thresholds of sour(0.0034+/-0.0021 N), sweet(0.027+/-0.012 M), and salty(0.027+/-0.014 M) were significantly higher than those of controls(0.0012+/-0.0007 N, 0.016+/-0.008 M, and 0.015+/-0.008 M, respectively)(P<0.05). 2)After hemodialysis, mean taste recognition thresholds of sour(0.0014+/-0.0011 N), sweet(0.015+/-0.011 M), and salty(0.020+/-0.011 M) were significantly decreased(P<0.05) but were not different from those of controls. 3) The mean recognition threshold for bitter was not improved after hemodialysis and was not different from that of controls. 4) The serum zinc concentration of patients with chronic renal failure was not different from that of controls. Finally, the mean taste recognition thresholds for sour, sweet, and salty were decreased in patients with end-stage renal disease and were improved after hemodialysis. The mean taste recognition threshold for bitter was not improved after hemodialysis and was not different from that of controls.