Purpose : The purpose of this study was to identify the relationship between fatigue and physiological factors in patients on hemodialysis. Method : Data were collected between June 1 and 7, 2003 using a structured questionnaire which included general characteristics, Visual Analogue scale and laboratory result. Result : Fatigue score changes is the mean of predialysis fatigue score was 4.36 and postdialysis fatigue score 4.66. There were statistically significant differences in score of postdialysis to sex, education and admission. The relationship between predialysis fatigue and interdialytic weight gain showed a positive correlation. The relationship between postdialysis fatigue and Cr showed a negative correlation. Conclusion : Nursing Management program should be developed to fatigue factors in patients on hemodialysis.