Whether a low platelet width is important or not needs to be judged according to the degree of lowness and cannot be generalized. Platelets are associated with hemostasis in the body, and the index, platelet distribution width, reflects the consistency of platelet volume size. A high platelet distribution width indicates inconsistent platelet size and volume, while a low platelet distribution width indicates that the patient has consistent platelet volume and size, but smaller than normal. This index can indirectly reflect the proliferation of the bone marrow megakaryocyte system. If the degree of low platelet distribution width is insignificant, it is generally not of much clinical significance. However, if it is significantly low, it indicates that the proliferation of myeloid megakaryocytes is inhibited, which is an important condition and the cause needs to be further investigated. In addition, because the platelet distribution width size is only one indicator of the platelet distribution width, a comprehensive analysis of blood function is needed with reference to the function and number of platelets.