Low serum levels of the carnitine in chronic uremic patients treated by hemodialysis is one of the causes of muscle weakness. In 50 patients with chronic renal failure treated by HD and in 13 nondialyzed patients EMG and measurement of nerve conduction velocity were performed. In 25 of 50 patients treated with HD and in 13 non-dialyzed patients serum concentration of free and total carnitine were measured. In HD patients serum level of carnitine was significantly lower as compared to the control group of healthy subjects and to the nondialyzed patients. In all patients the EMG investigations showed the traits of the neurogenic atrophy of the muscles. The correlation between the amplitude of muscle potentials and serum levels of carnitine suggests that the depletion of carnitine may play a role in severity uremic myopathy.