Leukemia m5b is acute monocytic leukemia, belonging to the M5 type of acute myeloid leukemia. Acute myeloid leukemia is a malignant tumor of the hematopoietic system, of which acute monocytic leukemia accounts for about 10%, with a low remission rate and easy to relapse. Acute monocytic leukemia is divided into two subtypes, M5a and M5b, according to the degree of differentiation. The M5a type is the undifferentiated type, which is dominated by primitive monocytes, with fewer naïve monocytes, and the peripheral blood is dominated by primitive monocytes. M5b type is partially differentiated, naive monocytes and primitive monocytes can be seen, the sum of the two accounted for the proportion of non-red lineage nucleated cell counts of 30% to 80%, peripheral blood is dominated by naive monocytes. Leukemia m5b is recommended to seek timely medical treatment, active examination and treatment.