It is certain that blood donation has an impact on the body, because blood donation is not a normal physiological process, but artificially separates the blood in the body and supplies it to patients in clinical need, so blood donation will have a certain impact on the human body. The most common effect is that after blood donation, the number of red blood cells in the body decreases, and the human body will have fatigue symptoms. When donating blood, the blood volume is less than110, which has little influence on the human body and sometimes has no obvious feeling. However, some people will have obvious fatigue symptoms after donating blood, and some people will have low fever after donating blood, which can also be encountered in clinic. Of course, both fatigue and low-grade fever are temporary for blood donors, and will gradually return to normal by strengthening nutrition after rest. Blood donation can also promote the metabolism of red blood cells in bone marrow and promote red blood cell hematopoiesis, so blood donation has an impact on the human body, but the impact is relatively small. From the perspective of social benefits, it is still necessary to advocate voluntary blood donation.