The reference value of average red blood cell volume for normal people is 82-100fl. low average red blood cell volume means below 82fl, which is common in iron deficiency anemia and thalassemia and other blood diseases. 1. Iron deficiency anemia: it is a kind of blood disease caused by insufficient iron intake or iron absorption disorder, chronic blood loss and other reasons. In this case, the body is unable to produce enough hemoglobin, and the volume of red blood cells produced is small, and the average volume of red blood cells will be low in routine blood tests. 2. Thalassemia: It is a kind of hereditary disease due to the disorder of synthesis of peptide chain of pearl protein. When the synthesis of pearl protein peptide chain is reduced, the body is unable to produce enough hemoglobin, and the volume of red blood cells produced is on the small side, and the average volume of red blood cells will be on the low side during routine blood tests. Patients should not rely on a single test result to determine a particular disease, and are advised to visit a hospital and cooperate with a physician for further treatment.