A platelet distribution width of 16.6 is normal. Platelet distribution width can indicate the dispersion of platelet volume and size, and the normal range of platelet distribution width is 15% to 17%. Platelet distribution width is related to the number of platelets and the degree of hematopoietic activity of bone marrow. When aplastic anemia occurs in the organism, platelet synthesis is impaired, the number of platelets decreases, and the distribution width of platelets decreases accordingly. If the organism suffers from acute myeloid leukemia, megaloblastic anemia, chronic myeloid leukemia, splenectomy, giant platelet syndrome, and thrombophilia, it will lead to a large number of irregular proliferation of blood cells including platelets, platelet size disparity, and the platelet distribution width will increase. If the width of platelet distribution deviates from the normal value, one should consult a doctor in time for a clear diagnosis and targeted treatment.