Low hematocrit predicts a decrease in hematocrit, and common causes include physiologic factors, anemia, leukemic malignancies The common causes are physiological factors, anemia, leukemia malignancy, etc. Erythrocyte hematocrit is also known as hematocrit, and hematocrit is an important factor in the formation of blood viscosity. 1. Physiological factors: After drinking too much water, blood is diluted and blood viscosity decreases, which will result in low hematocrit. When women are menstruating, the number of red blood cells decreases, resulting in a low hematocrit. 2. Anemia: When anemia occurs, hemoglobin concentration decreases and hematocrit also decreases. Common types of anemia include iron deficiency anemia, hemolytic anemia, megaloblastic anemia, aplastic anemia, and so on. 3. Leukemia: the main clinical feature of leukemia is hematopoietic dysfunction, which leads to the reduction of red blood cells, and then the hematocrit is low. 4. Malignant tumors: malignant tumors such as multiple myeloma, lymphoma, etc. can also lead to abnormal bone marrow function, which in turn leads to low hematocrit. There are other reasons for low hematocrit, so it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, and then give targeted treatment or therapy.