【Abstract】 Objective To study the 12 week aerobic exercise and drug intervention on patients with chronic heart failure combined with red cell distribution width, affect heart function and exercise capacity and determine the relationship between red cell distribution width and heart function and exercise capacity. Methods 152 patients with heart failure in our hospital were randomly divided into exercise group and the control group. The patients in the control group received routine anti heart failure drug education and did not change the patient's daily habits, regular exercise group in the control group on the basis of aerobic exercise, aerobic exercise for 12 weeks. The symptom limited exercise experiment to test the patient's exercise capacity was used before and after the experiment. The VO2 max parameters, maximum power parameters and exhaustive time were observed. The NYHA classification index for classification of cardiac function and left ventricular ejection fraction was determined by color Doppler ultrasonic diagnostic apparatus (LVEF parameter).The hemoglobin, red blood cell count, hematocrit and the red cell distribution width were measured. Results The red cell distribution width and parameters of cardiac function in grade NYHA and LVEF parameters were negatively correlated. VO2max parameters of red cell distribution width and movement parameters, maximum power parameters and exhaustive time parameter were negative. 12 weeks aerobic exercise intervention, exercise group LVEF parameters, VO2max parameters and the maximum power significantly increased. NYHA grading, heart rate and red cell distribution width significantly decreased. Conclusion There is a negative correlation between red cell distribution width and heart function in patients with chronic heart failure and exercise capacity. Aerobic exercise therapy can effectively reduce the red cell distribution width in patients with chronic heart failure on the basis of regular anti heart failure drug and effectively improve the heart function of patients and exercise capacity.