Low platelets may be a precursor to diseases such as aplastic anemia, acute leukemia, and primary thrombocytopenic purpura, but a single indicator does not make the diagnosis. The normal value of platelet count in blood is (100-300) × 10^9/L. When the platelet count is less than 100 × 10^9/L, it is thrombocytopenia. It is commonly seen in aplastic anemia, acute leukemia, acute radiation sickness, primary thrombocytopenic purpura, hypersplenism, disseminated intravascular coagulation, familial thrombocytopenia and other diseases. If there is thrombocytopenia, it may be a sign of these diseases, but a single test result cannot make a diagnosis, and it needs to be combined with the patient’s symptoms as well as other test results to finally confirm the diagnosis. It is recommended that the patient consults a professional doctor in time, and under the doctor’s guidance, the appropriate examination and treatment is carried out.