Pseudo Chediak-Higashi (PCH) granules are mainly common in acute myeloid leukemia and other subtypes of leukemia. Here, we found a patient diagnosed with precursor B-acute lymphoblastic leukemia (ALL) with PCH cytoplasmic granules, which was rarely seen in daily diagnosis. The morphology of the granules was different in transmission electron microscope (TEM) from cases reported before. There was a vesicle with various-sized particles surrounding the nucleus, and in addition to the particles, a multiple-layer membrane structure was also detected in the vesicle. F I G U R E 1 The morphology and periodic acid-Schiff (PAS) staining of giant inclusions in lymphoblastic cells. (A-D) Giemsa-Wright's staining of patient's bone marrow smear. The inclusions are located next to the nucleus, showing heterogeneous coloring. (E and F) PAS staining of lymphoblast in the bone marrow. The inclusions are mildly positive in lymphoblastic cells (as indicated by the arrow)